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Member 131317266-Jun-17 23:33

6-Jun-17 23:33

Hello,

i am trying to analyze the issue of missing data over my Datagridview in C#.

I am receiving data from Serial port with 5250000 (5,25 Mbps)& Splitting it over datagridview (Datatable). Simultaneously i am saving this data over PC using Binarywriter.

However when i am analysing my dumped data file over pc, i found almost 30% of data is missing between two intervals. My timer Event is 1 milisec & i am updating datagridview in timer tick.

So how i can get contineous stream of data both over datagrid view & write it in file to save over PC?

Possible Error is use of Serialport.BytesToRead method as its blocking type.

SO can anybody tell where exactly i am wrong?

My Code is as below:

<pre>using System;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO.Ports;
using System.IO;
using System.Threading;
using System.Diagnostics;
using System.Text.RegularExpressions;

namespace DataGridView
{
    public partial class DataGridView : Form
    {

        DataTable table = new DataTable("Sniffer Data Logger");
        byte[] buffer = new byte[5 * 1024];

        public DataGridView()
        {
            InitializeComponent();

            //Add Columns in the form
            table.Columns.Add("System Time");        // column to display system time
            table.Columns.Add("Source");             // column to display source i.e addr bus, data bus, reverse addr bus or reset & so on
            table.Columns.Add("T.S Begin");          // column to display beginning of timestamp
            table.Columns.Add("T.S End");            // column to display end of the timestamp
            table.Columns.Add("Duration (uS)");      // Add duration of the Frame
            table.Columns.Add("Length");             // column to dispaly length of the datafield
            table.Columns.Add("Data");               // column to display Data content of the protocol
            table.Columns.Add("CRC");                // CRC Check for frame valiadation
            table.Columns.Add("CRC_PC");             // CRC generated by PC         

            serialPort1.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived);
        }

        /*Load Form1 to show the results*/
        private void Form1_Load(object sender, EventArgs e)
        {

        }

        /*Port Data received event handler*/
        private void port_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            this.BeginInvoke(new EventHandler(Timer1_Tick));

        }

        /*Byte array to Hex conversion using string builder*/
        private string ByteArrayToHexString(byte[] data)
        {
            StringBuilder sb = new StringBuilder();
            foreach (byte b in data)
                sb.Append(Convert.ToString(b, 16).PadLeft(2, '0').PadRight(3, ' '));
            return sb.ToString().ToUpper().Replace(" ", "");
        }

        /*Update Datagrid View at each timer tick (zb. Timer Tick is 100mSec)*/
        private void Timer1_Tick(object sender, EventArgs e)
        {

                /*Read Data coming from ComPort Byte by Byte &store in the buffer*/
                int Bytes = serialPort1.BytesToRead;                            // Read Bytes coming from the Serial Port with data rate of 5.25 Mbps
                byte[] buffer = new byte[5 * 1024];                             // Store the bytes in buffer of Size 5KByte
                                                                                //Byte[] buffer = new byte[Bytes];                              // Read new coming bytes
                long read = serialPort1.Read(buffer, 0, Bytes);

                /*Binary Writer*/
                BinaryWriter writer = new BinaryWriter(File.Open("c:\\temp\\snifftimetick.dat", FileMode.Append));
                writer.Write(buffer);
                writer.Close();

                /*Check if buffer length is full*/
                if (read == buffer.Length)
                {
                    byte[] newbuffer = new byte[buffer.Length * 2];             // Double the buffer length i.e 5KB x 2 = 10KB
                    Array.Copy(buffer, newbuffer, buffer.Length);               // Copy the previous buffer data in to new buffer
                    newbuffer[read] = (byte)Bytes;                              // Read the new coming bytes from the serial port
                    buffer = newbuffer;                                         // show all data together in buffer
                    read++;

                }
            }

            /*Check if the incoming stream contains preamble "AA"*/
            DataRow row = table.NewRow();                                           // Insert New row in datagridview

            if (ByteArrayToHexString(buffer).Contains("AA"))
            {
                if (ByteArrayToHexString(buffer).StartsWith("AA"))                  // Check if buffer starts with "AA"
                {
                    switch (ByteArrayToHexString(buffer).Substring(6, 2))           // Switch statement to check if substring startswith CMD ID
                    {
                        // Case for "ABUS_L/R"
                        case "11":
                            table.Rows.Add(row);                                                // Add new row

                            row["Source"] = string.Format("{0}", "ABUS_L/R");                   // Insert source name in row
                            row["System Time"] = DateTime.Now.ToString("HH:mm:ss:fff");         // Insert time in row
                                                                                                //row["Source"] = ByteArrayToHexString(buffer).Substring(9, 2);     
                            row["T.S Begin"] = ByteArrayToHexString(buffer).Substring(8, 8);    // Insert TS Begin
                            row["T.S End"] = ByteArrayToHexString(buffer).Substring(16, 8);    // Insert TS End
                            row["Length"] = ByteArrayToHexString(buffer).Substring(24, 2);      // Insert length Field
                            row["Data"] = ByteArrayToHexString(buffer).Substring(26, 2);        // Insert Data field
                            row["CRC"] = ByteArrayToHexString(buffer).Substring(28, 2);         // Compare CRC field with Protocol & validate the information
                            row["CRC_PC"] = crc8.ComputeChecksum(buffer);                       // Compute & compare CRC generated by PC       
                            break;

                        // Case for "ABUS_RK"
                        case "12":
                            table.Rows.Add(row);                                                // Add new row

                            row["Source"] = string.Format("{0}", "ABUS_RK");
                            row["System Time"] = DateTime.Now.ToString("HH:mm:ss:fff");
                            //row["Source"] = ByteArrayToHexString(buffer).Substring(9, 2);

                            row["T.S Begin"] = ByteArrayToHexString(buffer).Substring(8, 8);
                            row["T.S End"] = ByteArrayToHexString(buffer).Substring(16, 8);
                            row["Length"] = ByteArrayToHexString(buffer).Substring(24, 2);
                            row["Data"] = ByteArrayToHexString(buffer).Substring(26, 2);
                            row["CRC"] = ByteArrayToHexString(buffer).Substring(28, 2);
                            row["CRC_PC"] = crc8.ComputeChecksum(buffer);
                            break;

                        // Case for "DataBus"
                        case "13":
                            table.Rows.Add(row);                                                // Add new row

                            row["Source"] = string.Format("{0}", "DataBus");
                            row["System Time"] = DateTime.Now.ToString("HH:mm:ss:ffffff");

                            //row["Source"] = ByteArrayToHexString(buffer).Substring(9, 2);

                            //row["T.S Begin"] = ByteArrayToHexString(buffer).Substring(8, 8);
                            //row["T.S End"] = ByteArrayToHexString(buffer).Substring(16, 8);

                            // Convert Timestamp values to Decimal UInt values
                            string ts1 = ByteArrayToHexString(buffer).Substring(8, 8);              // Assign new string for timestamp begin
                            UInt32 number = Convert.ToUInt32(ts1, 16);                              // convert Hex value to UINT32
                            UInt32 time1 = swap(number);                                            // Big Endian to Little Endian Conversion
                            double tmil1 = ((double)time1 / (double)1000);                          // Time in Mikrosecond
                            string res1_tmil = tmil1.ToString();

                            string ts2 = ByteArrayToHexString(buffer).Substring(16, 8);             // Assign new string for timestamp begin
                            UInt32 number1 = Convert.ToUInt32(ts2, 16);                             // convert Hex value to UINT32
                            UInt32 time2 = swap(number1);                                           // Big Endian to Little Endian Conversion
                            double tmil2 = ((double)time2 / (double)1000);
                            string res2_tmil = tmil2.ToString();

                            row["T.S Begin"] = time1;
                            row["T.S End"] = time2;
                            row["Duration (uS)"] = ((time2 - time1));                               // Calculate the duration of the Frame as per timestamps

                            row["Length"] = ByteArrayToHexString(buffer).Substring(24, 2);

                            // Convert string to integer data for counting the byte information in the string
                            string len = ByteArrayToHexString(buffer).Substring(24, 2);
                            int count = int.Parse(len, System.Globalization.NumberStyles.HexNumber);                            // Get integer value of the substring
                            row["Data"] = ByteArrayToHexString(buffer).Substring(26, count * 2);                                  // Count number of bytes based on count value
                            row["CRC"] = ByteArrayToHexString(buffer).Substring((26 + count * 2), 2);                              // Count 1 Byte of CRC after Length field
                            row["CRC_PC"] = crc8.ComputeChecksum(buffer).ToString("X2").ToUpper();
                            break;

                        // Case for "RESET" Signal
                        case "14":
                            table.Rows.Add(row);                                                // Add new row
                            row["Source"] = string.Format("{0}", "RESET");
                            row["System Time"] = DateTime.Now.ToString("HH:mm:ss:fff");

                            row["T.S Begin"] = ByteArrayToHexString(buffer).Substring(8, 8);
                            row["T.S End"] = ByteArrayToHexString(buffer).Substring(16, 8);
                            break;

                        // Default Case
                        default:
                            table.Rows.Add(row);                                                // Add new row
                            row["Source"] = string.Format("{0}", "ERROR_CMD_ID");
                            row["System Time"] = DateTime.Now.ToString("HH:mm:ss:fff");
                            int startIndex = 0;
                            string pattern = "AA";
                            string input = ByteArrayToHexString(buffer);
                            var regex = new Regex(pattern);
                            int endIndex = regex.Match(input, startIndex).Index;
                            int length = endIndex - startIndex;
                            row["Length"] = length;
                            break;

                    }

                }

                /*Check if buffer not startswith "AA"*/
                else if (!(ByteArrayToHexString(buffer).StartsWith("AA")))
                {
                    table.Rows.Add(row);                                                // Add new row

                    row["Source"] = string.Format("{0}", "ERROR_PA_POS");
                    row["System Time"] = DateTime.Now.ToString("HH:mm:ss:fff");
                    int startIndex = 0;
                    string pattern = "AA";
                    string input = ByteArrayToHexString(buffer);
                    var regex = new Regex(pattern);
                    int endIndex = regex.Match(input, startIndex).Index;
                    int length = endIndex - startIndex;
                    row["Length"] = length;

                }
            }

            /*Check if buffer not contains "AA"*/
            else if (!(ByteArrayToHexString(buffer).Contains("AA")))
            {
                table.Rows.Add(row);                                                // Add new row

                row["Source"] = string.Format("{0}", "ERROR_PA");
                row["System Time"] = DateTime.Now.ToString("HH:mm:ss:fff");
            }
            /*Update the Datattable*/
            dataGridView1.Update();

            /*Bind the Gridview with Source*/
            dataGridView1.DataSource = table;
        }

        /*Byte Swaping Function for Timestamp to convert Big Endian to Little Endian*/
        public static UInt32 swap(UInt32 value)
        {
            return (value & 0x000000FFU) << 24 | (value & 0x0000FF00U) << 8 |
         (value & 0x00FF0000U) >> 8 | (value & 0xFF000000U) >> 24;

        }

        /*CRC8 Implementation for received data*/
        public static class crc8
        {
            static byte[] table = new byte[256];
            const byte poly = 0xd5;

            public static byte ComputeChecksum(params byte[] bytes)
            {
                byte crc = 0;
                if (bytes != null && bytes.Length > 0)
                {
                    //if (!BitConverter.IsLittleEndian)
                    //{
                    //    Array.Reverse(bytes);
                    //}
                    foreach (byte b in bytes)
                    {
                        crc = table[crc ^ b];

                    }
                }

                return crc;
            }
            static crc8()
            {
                for (int i = 0; i < 256; i++)
                {
                    int temp = i;
                    for (int j = 0; j < 8; ++j)
                    {
                        if ((temp & 0x80) != 0)
                        {
                            temp = (temp << 1) ^ poly;
                        }
                        else
                        {
                            temp <<= 1;
                        }
                    }
                    table[i] = (byte)temp;
                }
            }

        }

        /*Button Functionalities*/
        /*Start Button*/
        private void btnStart_Click(object sender, EventArgs e)
        {

            /*Password Protection for Start*/
            if (txtUser.Text.ToString().CompareTo("test") == 0 & txtPass.Text.ToString().CompareTo("test") == 0)
            {
                txtUser.PasswordChar = '*';             // Once Logged in hide the User name
                txtPass.PasswordChar = '*';             // Once Logged in hide the Password
                MessageBox.Show("Login Successfull", "Start", MessageBoxButtons.OK, MessageBoxIcon.Information);        // Show message box

                /*Check whether user selected Online mode for Sniffing*/
                if (radioButton1.Checked == true)
                {

                    serialPort1.Open();         // Open the serial Port after putting correct Login ID & Password
                    label4.Visible = true;      // Indicate Green label
                    label3.Visible = false;     // Disable all other labels
                    label5.Visible = false;
                    timer1.Enabled = true;      // Enable the timer for counting time

                }
                else
                {
                    MessageBox.Show("Choose Online Mode / Data Mode", "Start", MessageBoxButtons.OK, MessageBoxIcon.Warning);    // Show Error Message
                }
            }
            else
            {
                label3.Visible = true;           // Show Error Label
                MessageBox.Show("Wrong Username/Password! \n Please try again!", "Login", MessageBoxButtons.OK, MessageBoxIcon.Error);
                txtPass.Text = "";
                txtUser.Text = "";
            }

        }
        /*Checkbox click to Show or Hide the Password (Not using in this Program)*/
        private void checkBox1_CheckedChanged(object sender, EventArgs e)
        {
            if (checkBox1.Checked == true)
            {
                txtPass.PasswordChar = (char)0;
                checkBox1.Text = "Show Password";
            }
            else
            {
                txtPass.PasswordChar = '*';
                checkBox1.Text = "Hide password";
            }
        }

        /*Stop Button*/
        private void btnStop_Click(object sender, EventArgs e)
        {
            serialPort1.Close();         // Close the serial Port
            timer1.Enabled = false;      // Disable the timer for counting time
            label3.Visible = true;
            label4.Visible = false;
        }

        /*Save / Export data to .Text File*/
        private void btnSave_Click(object sender, EventArgs e)
        {
            TextWriter writer = new StreamWriter(@"C:\temp\Sniffer_log.txt");        // Initiate streamwriter to write data from datagrid window
            label5.Visible = true;                                                  // Show Yellow Color label for saving file
            for (int i = 0; i < dataGridView1.Rows.Count - 1; i++)                          // Row count 
            {
                for (int j = 0; j < dataGridView1.Columns.Count; j++)               // count the columns 
                {
                    writer.Write("\t" + dataGridView1.Rows[i].Cells[j].Value.ToString() + "\t" + ";");      // write value of rows & columns with proper format
                }
                writer.WriteLine("");                                               // Write the data in the log file

            }
            writer.Close();                                                         // Close the writer
            MessageBox.Show("Data Saved");                                          // Show Message
            label5.Visible = false;                                                 // Disable data save Label
        }

        private void dataGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
        {

        }

        /*Clear the content of the datagridview*/
        private void btnclear_Click(object sender, EventArgs e)
        {
            table.Clear();
            table.DefaultView.RowFilter = null;                             // Disable all enabled filter options
        }

        /*Implementation of Filter property for particular rows*/
        private void button1_Click(object sender, EventArgs e)
        {
            table.DefaultView.RowFilter = "Length LIKE '*09*'";             // Filter data row containing length field of 9
            dataGridView1.Refresh();
        }

        /*Implemenation of Progress bar based on the buffer size. As buffer gets filled progress bar show green color*/
        private void progressBar1_Click(object sender, EventArgs e)
        {

        }

        /*Select Online Mode for Sniffer*/
        private void radioButton1_CheckedChanged(object sender, EventArgs e)
        {
            btnStart.Enabled = true;        // Enable Open port button
            btnLoad.Enabled = false;        // Disable Load button which is useful for offline mode
        }

        private void btnLoad_Click(object sender, EventArgs e)
        {

        }

        private void radioButton3_CheckedChanged(object sender, EventArgs e)
        {
            //serialPort1.Open();
        }

    }
}

Re: Missing data on Windows App form C#

Jochen Arndt7-Jun-17 1:46

Jochen Arndt

7-Jun-17 1:46

Using a timer is a bad idea. Data might get lost if there are more data send between two ticks than the internal buffer can hold (4096 bytes by default) and/or with high system load. The common method is using a thread that reads and processes incoming data (especially which high data rates like in your case). I suggest to use the BackgroundWorker Class (System.ComponentModel)[^].

However, the buffer size can be set with the SerialPort.ReadBufferSize Property (System.IO.Ports)[^].

If you still want to use a timer be aware that the smallest possible timer tick is system dependant (resolution of the system clock) which is used when passing a smaller value. The typical resolution is 15 ms.

There is also a possible buffer overflow in your code:

int Bytes = serialPort1.BytesToRead;
byte[] buffer = new byte[5 * 1024];                                                                                //Byte[] buffer = new byte[Bytes];
long read = serialPort1.Read(buffer, 0, Bytes);

The commented line is doing it right.

Re: Missing data on Windows App form C#

Member 131317267-Jun-17 2:47

Member 13131726

7-Jun-17 2:47

Ok. One more Thing is about using Invoke method.
What i want to achieve is :
1. Read data on Serial port
2. Store it in File over PC (as raw data file)
3. Show data in decoded form over datagridview

So how i can invoke this 3 processes? If i solve this it will be done i guess.

I tried possibility like:
1. Read serialport data using serialport.BytetoRead();
2. Write data in File over PC
Both 1 & 2 i called in serialdataEvent handler
3. Invoke Timer from serialdataevent handler

But its giving me exeption handler error.

Re: Missing data on Windows App form C#

Gerry Schmitz7-Jun-17 3:16

Gerry Schmitz

7-Jun-17 3:16

3 threads: 1 for the serial port; 1 for the file writer; and one for the "grid worker".

Create 2 concurrent queues; one for the file writer and one for the grid worker.

Serial reader writes to both queues; and invokes other threads if not "awake" at each queue write.

Workers run until their respective queues are exhausted; and restarted for "new work".

"(I) am amazed to see myself here rather than there ... now rather than then".
― Blaise Pascal

Re: Missing data on Windows App form C#

Jochen Arndt7-Jun-17 3:26

Jochen Arndt

7-Jun-17 3:26

When using a worker thread there is no need to user a timer. Read the data and write them to file within the worker thread and then pass the data to the GUI thread (using delegate).

You already use a threaded receive function: port_DataReceived().
Receive the data there instead of starting a timer.

I'm not very good in C# so I can't provide a full solution.

See for example this QA serial port using threading[^] and Basic serial port listening application[^].

Re: Missing data on Windows App form C#

Luc Pattyn8-Jun-17 13:44

Luc Pattyn

8-Jun-17 13:44

Hi,

your job is quite a challenge: with loads of data incoming at high rate and no way to stop the producer, the consumer (i.e. your PC program) needs to be designed and coded carefully and economically to obtain an acceptable probability of it keeping up with the producer under normal circumstances.

1. I do agree with what others said about using threads, not timers.

2. I do not like your approach of turning all data into strings, such conversion is time consuming and unnecessary, the one positive thing about it is it is easy and quite readable. If incoming data is binary, you should keep it binary at all times IMO. And your file should be binary too, unless there are forcing reasons against that.

3. Moreover, your code seems to be wasting huge amounts of computer cycles; there are dozens of calls to ByteArrayToHexString(buffer) all performing the same expensive job; and then a lot of them only are interested in a small part of the result, e.g. ByteArrayToHexString(buffer).Substring(16, 8); so why convert everything?
If you insist on having a conversion, either perform it once and store the result, or only convert the part you're interested in (i.e. pass startIndex and Length to the conversion method).

4. As you are basically performing two jobs (display and storage) and missing 30% of the data, it must be hard to figure out exactly where it goes wrong when it does. So I would suggest you concentrate on one job until that works perfectly; then do the other job, and finally combine them.

I hope this helps; I do realize my suggestions may imply a lot of work, and the need for a lot more code.

Luc Pattyn [My Articles] Nil Volentibus Arduum

Re: Missing data on Windows App form C#

Member 1313172611-Jun-17 20:41

Member 13131726

11-Jun-17 20:41

Hello,

Thank you for Reply.

I am now changing my Approach from timers to threads. But i want to update my datagridview suppose at every second. So do i just Need to call datagridview thread in timer?
I will store the result in string & then use same for Splitting. Basically i am sniffing protocol which have defined structure. So either i can use string Approach or i Need to read & check every Byte to match with my protocol structure. So to avoid this i am just converting them in to string & then Splitting in to substrings.
I will follow same.

Re: Missing data on Windows App form C#

Luc Pattyn12-Jun-17 6:15

Luc Pattyn

12-Jun-17 6:15

Hi again,

1. There is no such thing as "calling a thread". Every thread is running all the time, provided it isn't blocked and sufficient CPU resources are available. Thread code often consists of one big loop performing some calculations and then either waiting (=being blocked on some object, say a WaitHandle) or just testing for more work (=polling). When polling, make sure not to have it spin all the time, which means when no job is available, block it for at least a fraction of a second (e.g. with a Thread.Sleep). Best is to use an event-driven approach though.

2. A WinForms Control will try and repaint itself as soon as there is a need for that, e.g. when you scroll it, your code adds/modifies data to it, etc. You can request a repaint by calling its Invalidate() method, which does not guarantee an immediate repaint, it merely queues a request. If you insist on having a periodic repaint, just use a Windows.Forms.Timer and in its Tick handler just do myDGV.Invalidate(); However, a list Control that gets an item added does not need an explicit Invalidate, it will know a repaint is required all by itself.

3. A DataGridView is a complex and expensive Control, that may require a lot of CPU cycles. If all you need is a way to look at some data, without lots of user interaction, sorting, and the like, I would recommend you use a ListBox instead. And assuming you'll have hundreds of items in it, I would suggest you make it hold your byte arrays, not strings; ListBoxes indeed hold items, not just strings, and allocate a rectangular area for displaying each of those items. If you make it userdrawn (myLB.DrawMode = DrawMode.OwnerDrawFixed;), and provide a DrawItem handler, you can actually paint whatever you want it to paint inside its rectangle; that allows you to create very inexpensive columns and backgrounds. Finally setting myLB.TopIndex=myLB.Items.Count-1; each time you add an item to it will ensure your ListBox keeps scrolling up automatically.

The nice thing about this approach is you only spend CPU resources to rows that are actually visible, all rows that are off-screen or otherwise invisible will not have their DrawItem event firing.

If all this is new to you, I suggest you read up on ListBox, and maybe this could be a good example.

Smile | :)

Luc Pattyn [My Articles] Nil Volentibus Arduum

Re: Missing data on Windows App form C#

Member 1313172612-Jun-17 20:39

Member 13131726

12-Jun-17 20:39

Hello,

Thank you for Information. I will go thrigh it.

Meanwhile i was checking my Code with Debugger & i found that before completely reading whole buffer, my Byte Array is taking new Bytes due to which i am losing data.

So somwthing is missing or wrong in this Loop:

private void DoUpdate(object s,EventArgs e)
        {<br />
            /Read Data coming from ComPort Byte by Byte &store in the buffer/
            int Bytes = serialPort1.BytesToRead;                            // Read Bytes coming from the Serial Port with data rate of 5.25 Mbps
            byte[] buffer = new byte[Bytes];                                // Store the bytes in buffer
            //Byte[] buff = new byte[Bytes];                                // Read new coming bytes
            serialPort1.Read(buffer, 0, buffer.Length);                     // Read serialport data & store the received bytes in buffer till buffer length

<pre>
        /*Write data from buffer to file on temp folder*/
        //writeData(buffer,0,buffer.Length);<br />
        /*Convert & store the result in string*/
        result = ByteArrayToHexString(buffer);                             // Store the result in string

        for (int i = 0; i <= buffer.Length; i++)
        {
            processData();                                                     // Call the function process data to update the Datagridview<br />
            return;
        }

    }</pre>

I tried using while Loop- (Read==buffer.length) but ist not giving me desired Output. Rather ist copying same data again & again.

I am updating my datagridview in processData().

Re: Missing data on Windows App form C#

Luc Pattyn12-Jun-17 23:42

Luc Pattyn

12-Jun-17 23:42

Hi,

1. the Visual Studio Debugger isn't very good at dealing with real-time applications, when you set breakpoints and are single-stepping, the whole timing of your code is ruined.
I recommend you use logging instead, please read my article: A simple logging scheme[^].

2. I found a better example for userdrawn listboxes: my article: Asynchronous operations run on ThreadPool threads[^]. The topic itself of that article should be of interest to you too.

3. There might be an issue of the DataReceived handler not always executing on the same thread, and hence, one handler execution possibly overlapping a previous one. That too is touched on in the latter article.

4. As far as your latest code goes, you just can't call processData(); for each and every byte; it is bound to include a task switch (some Invoke or BeginInvoke) and Windows cannot possibly be switching threads at the same pace as your serial data bytes are coming in.

5. It might be useful to tweak the data source for now (if doable), so predictable data is being generated e.g. numbered packets containing a fixed number of incrementing byte values; in my experience that facilitates the debugging a lot as any deviation at the reception side would be noticed quite easily.

In summary, I urge you to rely on logging; to include the thread number in every log message (and check they are acceptable); to have a log message at the start and the end of the DataReceived handler (and more); and to be fully aware of your CPU load. And please drop the DGV, just get the reception of your data solved without wasting time in displaying it; when that works, start solving the display problem, at best with a ListBox.

Smile | :)

Luc Pattyn [My Articles] Nil Volentibus Arduum

Json parser error when converting iphone images from bytes to base64 string in a MVC JsonResult

jkirkerx6-Jun-17 10:22

jkirkerx

6-Jun-17 10:22

So I'm storing some images in a file. I get the bytes, and convert the bytes to a Base64 string, that I place in a model that I return as Json.

At first everything was working fine with test images. Then I started using the customer images and pictures off my iPhone 6 and that's where the trouble began.
I get this parser error on the JQuery side, in which I isolated down to the Base64 string of the image.
So I have some bad chars that need to be formatted or converted.

I'm lost here ....
I have the replace statements that I added, but still get the error.
I think the pad right is not required.
I took the plain base64 string and pasted it into Best Online Base64 to Image converter and the image rendered fine.
I searched for JSON encoding, and got the replace chars.

Any point in the right direction would be appreciated.

picture.Base64 is a string
picture.Data is byte[]

public async Task<JsonResult> json_load_portfolio_picture(int PictureID, string PictureName)
{
      model_portfolio_image picture = io_portfolio_images.Load_Portfolio_Picture(PictureID);
      if (picture != null )
      {
          picture.Base64 = Convert.ToBase64String(picture.Data, 0, picture.Data.Length).Replace("/", "-").Replace("+", "_").Replace("=", "");
          picture.Base64 = picture.Base64.PadRight(picture.Base64.Length + (4 - picture.Base64.Length % 4) % 4, '=');
      }           

      await Task.Delay(1);
      return Json(picture, JsonRequestBehavior.AllowGet);
}

If it ain't broke don't fix it

Re: Json parser error when converting iphone images from bytes to base64 string in a MVC JsonResult [solved]

jkirkerx6-Jun-17 12:49

jkirkerx

6-Jun-17 12:49

Well I had a number of issues that just compounded the problem.

First after I posted the page back with the wrong picture data ( A picture in which I used JavaScript to capture page form data and just converted the selected image to a base64 string and stuffed it in a textbox to postback later), I used the wrong data or bytes to store the image in the database (The original and not the copy). I should of used the bytes from the new Graphic after resizing. This got rid of the iPhone data (EXIF stuff) that was in the image stream. So now my Base64 string starts with that

iVBOR

instead of

/9

After that, I searched everywhere on how to UTF8 a Base64 string and could not find anything on the subject. So I created a new JsonResult and set the max limit, content type and encoding and returned that object instead.

[HttpPost]
public async Task<JsonResult> json_load_portfolio_picture(int PictureID, string PictureName)
{
   model_portfolio_image picture = io_portfolio_images.Load_Portfolio_Picture(PictureID);
   if (picture != null)<br />
      picture.Base64 =  Convert.ToBase64String(picture.Data, Base64FormattingOptions.None).Trim();            

         JsonResult jResult = new JsonResult()
         {
            Data = picture,
            JsonRequestBehavior = JsonRequestBehavior.AllowGet,
            ContentEncoding = Encoding.UTF8,
            MaxJsonLength = 50000000,
            ContentType = "application/json"
         };

         await Task.Delay(1);
         return jResult;
  }

If it ain't broke don't fix it

Re: Json parser error when converting iphone images from bytes to base64 string in a MVC JsonResult [solved]

Richard Deeming7-Jun-17 0:57

Richard Deeming

7-Jun-17 0:57

Why have you got await Task.Delay(1); in there?

If it's just to get rid of the "async method lacks await" warning, then it would be simpler to remove the async modifier:

public JsonResult json_load_portfolio_picture(int PictureID, string PictureName)

You don't have any other await calls in the method, so there's no point making it async. Smile | :)

"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer

Re: Json parser error when converting iphone images from bytes to base64 string in a MVC JsonResult [solved]

jkirkerx7-Jun-17 6:33

jkirkerx

7-Jun-17 6:33

I knew somebody was going to ask that.
Because it was the minimum requirement to make the task async. But that task really doesn't need to be async since I'm getting information.

If it ain't broke don't fix it

Create a chart in PowerPoint using C#.

Member 126813284-Jun-17 22:30

Member 12681328

4-Jun-17 22:30

How to Create a chart in PowerPoint using C#.Suppose i have the date in x axis and some arbitrary values in Y axis?

Re: Create a chart in PowerPoint using C#.

OriginalGriff4-Jun-17 22:43

OriginalGriff

4-Jun-17 22:43

Google is your friend: Be nice and visit him often. He can answer questions a lot more quickly than posting them here...

A very quick search using your subject as the search term gave over half a million hits: How to Create a chart in PowerPoint using C# - Google Search[^]

In future, please try to do at least basic research yourself, and not waste your time or ours.

Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
AntiTwitter: @DalekDave is now a follower!

custom controls not binding wpf

Member 112967764-Jun-17 7:52

Member 11296776

4-Jun-17 7:52

Hi everybody,

i have created a user control combined with textbox and label.
i created text and label register to modify the label and textbox.
when i tried to bind the text and label nothing is shown.

here's the xaml of the user control:

<UserControl x:Class="Gestione_WPF.LabelledTextBox"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:Gestione_WPF"
             mc:Ignorable="d" 
             d:DesignHeight="50" d:DesignWidth="200">
    <Grid Background="White" FlowDirection="RightToLeft">
       <Label x:Name="lbl" Content="{Binding Label, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"  HorizontalAlignment="Left" Background="{StaticResource gradientBrushTabControlHeader}">
            <Label.Style>
                <Style TargetType="Label">
                    <Setter Property="Template">
                        <Setter.Value>
                            <ControlTemplate TargetType="Label">
                                <StackPanel Orientation="Horizontal">
                                    <Border Background="{StaticResource ResourceKey=gradientBrushSegmentedTabItem}" Width="200" BorderThickness="0,0,0,0">
                                        <StackPanel Orientation="Horizontal">
                                            <Viewbox StretchDirection="DownOnly" Stretch="Uniform">
                                            <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" RecognizesAccessKey="True" TextBlock.FontSize="14" TextBlock.Foreground="#FFFFFF" Margin="5">
                                                <ContentPresenter.Effect>
                                                    <DropShadowEffect BlurRadius="0.0"
                                                  Color="#032A6B"
                                                  Direction="90"
                                                  Opacity="1"
                                                  ShadowDepth="1" />
                                                </ContentPresenter.Effect>
                                            </ContentPresenter>
                                            </Viewbox>
                                        </StackPanel>
                                    </Border>
                                </StackPanel>
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </Label.Style>
        </Label>
        <TextBox x:Name="txt" Text="{Binding Text, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Width="120" HorizontalAlignment="Right">
            <TextBox.Style>
                <Style TargetType="TextBox">
                    <Setter Property="Template">
                        <Setter.Value>
                            <ControlTemplate TargetType="TextBox">
                                <Border CornerRadius="0,0,0,50" BorderBrush="Black" Background="White" BorderThickness="0">
                                    <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" RecognizesAccessKey="True" TextBlock.FontSize="14" TextBlock.Foreground="#FFFFFF" Margin="5">
                                        <ContentPresenter.Effect>
                                            <DropShadowEffect BlurRadius="0.0"
                                                  Color="#032A6B"
                                                  Direction="90"
                                                  Opacity="1"
                                                  ShadowDepth="1" />
                                        </ContentPresenter.Effect>
                                    </ContentPresenter>
                                </Border>
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </TextBox.Style>
        </TextBox>
    </Grid>
</UserControl>

here's the usercontrol.cs:

public partial class LabelledTextBox : UserControl
   {
       public LabelledTextBox()
       {
           InitializeComponent();
           this.DataContext = this;
       }

       public override void OnApplyTemplate()
       {
           base.OnApplyTemplate();
       }

       public static readonly DependencyProperty LabelProperty = DependencyProperty.Register("Label", typeof(string), typeof(LabelledTextBox), new PropertyMetadata(null));
       public string Label
       {
           get { return (string)this.GetValue(LabelProperty); }
           set { this.SetValue(LabelProperty, value);}
       }

       public static readonly DependencyProperty TextProperty = DependencyProperty.Register("Text", typeof(string), typeof(LabelledTextBox), new PropertyMetadata(null));
       public string Text
       {
           get { return (string)this.GetValue(TextProperty); }
           set { this.SetValue(TextProperty, value); }
       }
   }

and here's the implmentation:

<controls:LabelledTextBox Label="{Binding Hello}" Text="{Binding World}"/>

Why the binding not showing? if the label i'm doing without binding it works, but the text don't and i can't write inside the textbox.

Re: custom controls not binding wpf

Gerry Schmitz5-Jun-17 5:36

Gerry Schmitz

5-Jun-17 5:36

So; you're saying you have properties called "Hello" and "World" somewhere?

Did you implement the INotifyPropertyChanged interface?

"(I) am amazed to see myself here rather than there ... now rather than then".
― Blaise Pascal

Re: custom controls not binding wpf

Member 112967765-Jun-17 18:30

Member 11296776

5-Jun-17 18:30

I did implement INotifyPropertyChanged but i finally solved my problem
i remove this.DataContext = this; from the user control
and added relative reference
to label content:
Content="{Binding Label, RelativeSource={RelativeSource AncestorType=UserControl}}"
and textbox text:
Text="{Binding Text,RelativeSource={RelativeSource AncestorType=UserControl}, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"

Configure Remote Machine's IP in C# Service At Install Time

Django_Untaken3-Jun-17 22:58

Django_Untaken

3-Jun-17 22:58

Hi there. I have following scenario
- one machine with a service installed (machine 1)
- one remote machine with public ip (machine 2)
- one machine with web application (machine 3)

All these machines could be in the same premises or in different. Since all of these machines and their respective software could be installed in any order, I don't know how to get machine 2's IP. Because my service on machine 1 will use this IP to upload data to it. And, of course, web application on machine 3 will display this data.

Any idea what API/library could I use on machine 1 to recieve machine 2's IP? Thanks for anything you share.

Re: Configure Remote Machine's IP in C# Service At Install Time

Eddy Vluggen4-Jun-17 2:55

Eddy Vluggen

4-Jun-17 2:55

The user will have to enter it; there's no way that any api or library could "guess" which computer is meant with "machine 2".

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Re: Configure Remote Machine's IP in C# Service At Install Time

Gerry Schmitz4-Jun-17 4:45

Gerry Schmitz

4-Jun-17 4:45

Why don't you have machine 2 login to machine 1 and upload (i.e. FTP); instead of 1 calling 2, etc.

A scheduler on #2 and an event / file handler on #1 should suffice; based on your description.

"(I) am amazed to see myself here rather than there ... now rather than then".
― Blaise Pascal

Report cant be display on report viewer page in c#.net windows form

Member 132383512-Jun-17 22:31

Member 13238351

2-Jun-17 22:31

//Report Load page code using dataset
private void RPT_SupplierPer_Load(object sender, EventArgs e)
{
crystalReportViewer1.ReportSource = null;
DataTable dt = new DataTable();
SqlConnection con = new SqlConnection(cs.cstring());
con.Open();
SqlCommand cmd = new SqlCommand("RPT_Sup_All", con);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@id",ID);
SqlDataAdapter da = new SqlDataAdapter();
DataSet ds = new System.Data.DataSet();
//SupplierPer sp = new SupplierPer();
//da.Fill(ds);
// ds.Tables[0].TableName="RPT_Sup_All";
SupplierPer sp = new SupplierPer();
sp.Database.Tables[0].SetDataSource(ds.Tables[0]);

sp.SetDataSource(ds);
crystalReportViewer1.ReportSource = sp;
crystalReportViewer1.Refresh();

}
//print button code
private void btnPrint_Click(object sender, EventArgs e)
{
int id = Convert.ToInt16(txt_id.Text);
RPT_SupplierPer pt = new RPT_SupplierPer(id);
pt.Show();
}

Re: Report cant be display on report viewer page in c#.net windows form

User 41802543-Jun-17 3:32

User 4180254

3-Jun-17 3:32

You have already posted this in Question section.

modified 20-Sep-20 21:01pm.

How to solve 2 js script file crash problem

Member 130563031-Jun-17 16:22

Member 13056303

1-Jun-17 16:22

My project would not run probably since i have 2 js file are crashing, but these 2 js files are important in my project and cant throw it. how can i solve this by other ways. TQ Smile | :)

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