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DataGridView removing rows takes forever

shultas2-Aug-06 10:18

2-Aug-06 10:18

Hi everyone,

I have this small project. It reads from a file and populates a DataGridView. It has been working great when there were only 100 or 200 rows, but now there are 750 and it doesn't work well at all. I'm not sure what I am doing wrong.

When you first enter the page, there is a "SYNC" button. This opens the file, reads from it and populates the datagridview. Well, you can hit SYNC as many times as you want. What I am doing is when you press that button, clear the datagridview, and then re-populate it. I have tried DataGridView1.Rows.Clear(), and I have also tried ForEach loops that run a Rows.Remove() and Rows.RemoveAt() with no luck. I have 751 rows in there, and I have a message box pop up before it begins the Rows.RemoveAt() routine, then another message box that pops up after the foreach loop. It is taking like 30 seconds (I'm on a very very fast machine) to do this, and 98% of my system resources go to it. I'm not sure if it is trying to sort, or redraw or do something each time it deletes a row out of there or what. When the Rows.RemoteAt() routine finishes it has done what needed to be done (cleared out the datagridview completely), but it just takes way too long. I'm not sure exactly what it is that I can do to speed this up?? Any help would be extremely appreciated.

VB6 InputBox in C#

Kasic Slobodan2-Aug-06 10:17

Kasic Slobodan

2-Aug-06 10:17

I need to create a form to act as InputBox like in VB6.
When I write, string temp = InputBox.Show(); it displays the form where I need to insert some text and click ok so that temp variable is set to text entered in InputBoxes text field.
I want to design each of my InputBoxes from the forms I added to my Project.

How can I make this kind of form?

Re: VB6 InputBox in C#

Ennis Ray Lynch, Jr.2-Aug-06 10:38

Ennis Ray Lynch, Jr.

2-Aug-06 10:38

Make the form of type dialog. Then when you show the form use ShowDialog instead of Show. You can then check the DialogResult to see what action the user returned. Create the form any way you want.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

Re: VB6 InputBox in C#

Kasic Slobodan2-Aug-06 11:47

Kasic Slobodan

2-Aug-06 11:47

Thanks, that helped a lot.
Becouse I don't want to create an instance outside the InputBox, I've created a method inside the form.

public static string InputBox()<br />
		{<br />
			string tmp = "-1";<br />
			frmReason reason = new frmReason();<br />
			reason.ShowDialog();<br />
<br />
			if (reason.DialogResult == DialogResult.OK)<br />
			{<br />
				tmp = txtReason.Text;<br />
			}<br />
<br />
			return tmp;<br />
		}

This way I just need to call InputBox method: MessageBox.Show(frmReason.InputBox()); and I will get a form, write any text, and after clicking on ok (or enter) MessageBox will Show that text.

Thank you Ennis, very much.

Best way to debug

Tom Wright2-Aug-06 9:58

Tom Wright

2-Aug-06 9:58

I'm at a position where I cannot step thru my code to see where my problem is at. So I've got message boxes everywhere catching exception. So what is the best way to debug when you can't be there. Right now I'm catching the exception showing the message, the source, and the stack trace. Which I must admit is a little confusing. Any other suggestions.

Thanks

Tom Wright
tawright915@yahoo.com

Re: Best way to debug

Paul Voicu2-Aug-06 10:06

Paul Voicu

2-Aug-06 10:06

Why do you say you cannot debug through your code?

I think you could use

catch (Exception ex)
{
System.Diagnostics.Trace.WriteLine(ex.Message + " " + ex.StackTrace);
}

Re: Best way to debug

Tom Wright2-Aug-06 11:36

Tom Wright

2-Aug-06 11:36

I'm sorry, I meant I cannot step thru my code to see where my problem is at. Reason is this is socket app that requires a secured connection and that is on a network on the east coast.....I'm in the midwest.

Currently I am do the try and catch but putting it to a message box instead of the Trace function. I'll try that and see what the results are.

Thanks

Tom Wright
tawright915@yahoo.com

Re: Best way to debug

Paul Voicu2-Aug-06 11:40

Paul Voicu

2-Aug-06 11:40

When you use Trace you can have the code running without pressing the OK of the MessageBox and writing down the message on a piece of paper, while all the messages are going to be written in the Output window, so I would say it's more convenient.

I hope it helps.

Cheers

Pen and Paper

Ennis Ray Lynch, Jr.2-Aug-06 10:39

Ennis Ray Lynch, Jr.

2-Aug-06 10:39

It is the most arduous but it really works when it has too.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

How do I print the contents of a pictureBox

michmela442-Aug-06 9:07

michmela44

2-Aug-06 9:07

Hi. I'm very new to Visual C#. I was wondering if someone could help me print the contents of a pictureBox.

I would like to be able to print just the image and be able to control the size of the image as well as the location of the image on the page.

Please help if you can.

Use a printer

Ennis Ray Lynch, Jr.2-Aug-06 9:34

Ennis Ray Lynch, Jr.

2-Aug-06 9:34

Actually there are some very helpful tutorials on how to print bitmaps in C# available by searching google.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

Re: How do I print the contents of a pictureBox

stancrm2-Aug-06 20:02

stancrm

2-Aug-06 20:02

...
PrintDocument printDoc = new PrintDocument();
printDoc.PrintPage += new PrintPageEventHandler(printDoc_PrintPage);
printDoc.Print();
...

private void printDoc_PrintPage(object sender, PrintPageEventArgs e)
{
	PictureBox picBox = new PictureBox();
	picBox.Image = Image.FromFile(@"c:\mypic.jpg");

	e.Graphics.DrawImage(picBox.Image, 5, 5);
}

A better way than multiple case in switch statement

allenmpcx2-Aug-06 9:00

allenmpcx

2-Aug-06 9:00

Hello. I have the following function:

<br />
public BaseClass SpawnClass( ObjectType type )<br />
{<br />
  BaseClass retval = null;<br />
<br />
  float X = 5;<br />
  float scale = 0.3429f;<br />
<br />
  switch(type)<br />
  {<br />
    case ObjectType.Class1:<br />
    {<br />
       retval = new Class1(X,scale);<br />
       break;<br />
    }<br />
<br />
    case ObjectType.Class2:<br />
    {<br />
       retval = new Class2(X,scale);<br />
       break;<br />
    }<br />
<br />
    case ObjectType.Class3:<br />
    {<br />
       retval = new Class3(X,scale);<br />
       break;<br />
    }<br />
  }<br />
<br />
  return retval;<br />
}<br />

I have about 11 classes but I didn't want this to get too long. This works, but it's very ugly. Is there a better way to do this? I've thought about the "Gang of Four" design patterns, but I'm not sure if they would be less ugly. I noticed the TypeConverter class, but I don't know how to use it. Any suggestions?

I love to program!

Re: A better way than multiple case in switch statement

vineas2-Aug-06 9:12

vineas

2-Aug-06 9:12

Assuming the constructors are identical, I'd probably do something like:

public BaseClass SpawnClass(System.Type type)
{
  float X = 5;
  float scale = 0.3429f;

  return (BaseClass) type.InvokeMember(type.FullName, System.Reflection.BindingFlags.CreateInstance, null, null, new object[] {X, scale});
}

That should work from what I remember, but it may need some tweaks to be work correctly.

-----
In the land of the blind, the one eyed man is king.

Re: A better way than multiple case in switch statement

allenmpcx2-Aug-06 9:29

allenmpcx

2-Aug-06 9:29

That function looks like it depends on System.type, however the function I have depends on a custom enumeration (ObjectType). Would this way still work? Would there be a way to create a type using a string?

I love to program!

Re: A better way than multiple case in switch statement

Stefan Troschuetz2-Aug-06 10:04

Stefan Troschuetz

2-Aug-06 10:04

allenmpcx wrote:
Would there be a way to create a type using a string?

Activator.CreateInstance

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning." - Rick Cook

www.troschuetz.de

Re: A better way than multiple case in switch statement

allenmpcx2-Aug-06 10:00

allenmpcx

2-Aug-06 10:00

nevermind on that. Your method worked perfect because I can call Type.GetType() and pass in a string to get the type, so thats exactly what I did. Thanks a lot.

I love to program!

Little Endian vs Big Endian [modified]

seq-2-Aug-06 8:16

seq-

2-Aug-06 8:16

Hey guyz! I have a question how do I change in C# a number from such B8B80C00 byte-ordering into such one: 000CB8B8

Any help would be appreciated..

Regards,
Pawel

-- modified at 14:24 Wednesday 2nd August, 2006

Re: Little indian vs Big Indian [modified]

Drew McGhie2-Aug-06 8:19

Drew McGhie

2-Aug-06 8:19

Try spelling it right. its "endian," referring to the end of the significant bit. A quick google search should do you just fine.

-- modified at 14:19 Wednesday 2nd August, 2006

Re: Little indian vs Big Indian

Guffa2-Aug-06 9:04

Guffa

2-Aug-06 9:04

"Mmmmmm. Juicy Fruit."
-- Big indian (Chief Bromden)

Wink | ;)

---
b { font-weight: normal; }

Re: Little Endian vs Big Endian

Ennis Ray Lynch, Jr.2-Aug-06 8:25

Ennis Ray Lynch, Jr.

2-Aug-06 8:25

The IPAddress class provides methods with that functionality for several types.

A man said to the universe:
"Sir I exist!"
"However," replied the Universe, "The fact has not created in me A sense of obligation."

-- Stephen Crane

Re: Little Endian vs Big Endian

seq-2-Aug-06 8:29

seq-

2-Aug-06 8:29

ok guyz thx for the answer I found on google what I was looking for.. before that I couldnt find because I spelt it incorrect ;] thx for help anyway

Re: Little Endian vs Big Endian

engsrini2-Aug-06 8:33

engsrini

2-Aug-06 8:33

<br />
 string str = "000CB8B8";            <br />
<br />
            char[] ch=str.ToCharArray();<br />
            <br />
            string strev = "";<br />
            for (int i = (ch.Length-1); i >= 0; i--)<br />
            {<br />
                strev += ch[i].ToString();<br />
            }<br />
reversed string will be on strev<br />

Re: Little Endian vs Big Endian

Guffa2-Aug-06 8:52

Guffa

2-Aug-06 8:52

Reversing the nibbles won't correctly change the endianess of the number. You have to reverse the bytes:

string number = "000CB8B8";

string swapped = string.Empty;
for (int i = number.Length - 2; i >= 0; i -= 2) {
   swapped += number.Substring(i, 2);
}

---
b { font-weight: normal; }

Typed Datasets vs. Custom Classes

econner2-Aug-06 8:13

econner

2-Aug-06 8:13

I am looking for suggestions/pros/cons of using typed datasets vs. custom classes for my DAL/BLL.

Anyone have any thoughts on eXpress Persistance Objects from DevExpress or dOOdads from MyGeneration software?

Any other solutions?

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