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Re: how can i get min value in datatable with distinct items using loops

TnTinMn8-Feb-14 6:54

TnTinMn

8-Feb-14 6:54

This looks like homework. Show what you have tried and explain your problems.

To get you started here is one possible way to get the minimum values.

Loop through the rows and store the minimum value for each unique "item" value. You can use a Dictionary<string, int=""> to store these unique items and the value. If the Dictionary contains the "item", test the value and store the minimum value; if it does not contain the "item", add it.

This is not the complete solution, so do not come back and say its does not work.

Re: how can i get min value in datatable with distinct items using loops

Mycroft Holmes8-Feb-14 13:31

Mycroft Holmes

8-Feb-14 13:31

Do some research into GROUP BY and the MIN operator

Select Item, min(value) from table
Group By Item

Never underestimate the power of human stupidity
RAH

Re: how can i get min value in datatable with distinct items using loops

Md Nazmoon Noor13-May-14 3:21

Md Nazmoon Noor

13-May-14 3:21

sounds like a homework.

SSH Connection to Cisco Router

sikas_Cisco8-Feb-14 4:36

sikas_Cisco

8-Feb-14 4:36

Hello All,

I'm looking for a way to connect to a Cisco Router via SSH and then interpret the output to perform different operations based on the output, i.e. username/password incorrect, enable mode, etc ...

I have already been able to achieve this using TELNET, but now I need to migrate to SSH.

Best Regards,
Sikas.

Re: SSH Connection to Cisco Router

Richard MacCutchan8-Feb-14 5:28

Richard MacCutchan

8-Feb-14 5:28

See https://www.google.com/search?q=c%23+ssh[^].

Veni, vidi, abiit domum

Re: SSH Connection to Cisco Router

sikas_Cisco8-Feb-14 5:34

sikas_Cisco

8-Feb-14 5:34

I already searched, but didn't find anything useful!

Best Regards,
Sikas.

Re: SSH Connection to Cisco Router

Richard MacCutchan8-Feb-14 5:37

Richard MacCutchan

8-Feb-14 5:37

There were lots of links in the search I did. And given that your question lacks any real detail it is impossible to offer anything more.

Veni, vidi, abiit domum

Re: SSH Connection to Cisco Router

dharmegh9-Feb-14 19:23

dharmegh

9-Feb-14 19:23

just for testing

Attributes Help: Defining an item list in an attribute

helkhoury7-Feb-14 20:29

helkhoury

7-Feb-14 20:29

I am writing a program which will connect to a I2C to USB controller. I am using WPF.
I decided to create a Device class to contain the hardware description and all its attributes so I can use them to display properties and have the end user modify the settings of the hardware.
I have most of the above working, except 2 attributes.
Most attributes are strings or int or byte, etc... so they are easy to work with, like the example below:

private string _name;
       [Category("General")]
       [ReadOnly(false)]
       [DisplayName("Module Name")]
       [Description("Enter descriptive string ")]
       public string Name { get { return _name; } set { _name = value; OnPropertyChanged("Module Name"); } }

The 2 attributes I am having a hard time with need to have a list to populate.
So I read the hardware setting, and it returns that it supports I2C, SPI, and UART.
Now I want to be able to pass those to the "CommunicationType" attribute, and have it display as a list in the properties window.
To see if my program is working, I created the following class:

public class CommunicationType : IItemsSource
{
    public ItemCollection GetValues()
    {
        ItemCollection sizes = new ItemCollection();
        sizes.Add((int)PP_COM_Wrapper.enumInterfaces.I2C, "I2C");
        sizes.Add((int)PP_COM_Wrapper.enumInterfaces.ISSP, "ISSP");
        sizes.Add((int)PP_COM_Wrapper.enumInterfaces.JTAG, "JTAG");
        sizes.Add((int)PP_COM_Wrapper.enumInterfaces.SPI, "SPI");
        sizes.Add((int)PP_COM_Wrapper.enumInterfaces.SWD, "SWD");
        sizes.Add((int)PP_COM_Wrapper.enumInterfaces.SWD_SWV, "SWD SWV");
        return sizes;
    }
}

Then in the attribute, I have the following:

private int _comtype;
       [Category("Settings")]
       [ReadOnly(false)]
       [ItemsSource(typeof(CommunicationType))]
       [DisplayName("Communication Type")]
       public int CommunicationType { get { return _comtype; } set { _comtype = value; OnPropertyChanged("Communication Type"); } }

So when I run it, it gives the user the possibility to select from a drop down, one of the communication types.
Now the question is, how do I populate it programmatically. Some of the hardware only supports I2C and SPI, so I only want to populate the list with 2 items based on the hardware.

Any guidance or examples are greatly appreciated.
Thanks,
H-

modified 8-Feb-14 2:56am.

Using of Abstract class and Interface class

Rupaswathi7-Feb-14 19:06

Rupaswathi

7-Feb-14 19:06

Hi all,

Can any one help me how to use Abstract class and Interface class in developing web application using c# language.

Thanks

Re: Using of Abstract class and Interface class

Richard MacCutchan7-Feb-14 22:10

Richard MacCutchan

7-Feb-14 22:10

See Abstract Class versus Interface[^].

Veni, vidi, abiit domum

C# dll import

Member 42110407-Feb-14 5:40

Member 4211040

7-Feb-14 5:40

Hi,

I have a strange problem when calling one of my C++ dll functions from within C# code. Even though I have a work around but it is not making sense to me what caused the problem in the first place and would like to understand why.

I am writing below a very simple code that produces the problem:
Basically, My dll function returns a pointer to a null terminate string (const char *) that I would like to import it as a string in c# code.

The c++ DLL function :

C++

const char* ReturnSomeString()
{
    static string result="The string";
    return result.c_str();
}

The C# code:

[DllImport(@"thedll.dll", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.Cdecl)]
[return:MarshalAs(UnmanagedType.LPStr)]
public extern static string ReturnSomeString();

public void function()
{
  string result = ReturnSomeString();
}

When I run the c# code, sometimes it works, sometimes the result is garbage and most of the times it crashes with with exception message :

An unhandled exception of type 'System.AccessViolationException' occurred in theapplication.exe
Additional information: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.

As I mentioned, I have some couple work arounds but still want to understand why the above methodology does not work.

Work around 1:
---------------------
change the C++ code to not to use string class and just use the standard ansi char[] keeping the C# code unchanged.

Work around 2:
-----------------------
Keep the C++ code as is (using string class) but modify C# code:

[DllImport(@"thedll.dll", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.Cdecl)]
public extern static IntPtr ReturnSomeString();

public void function()
{
  string result = Marshal.PtrToStringAnsi(ReturnSomeString());
}

Please help me explaining what is wrong with the first method.

Thanks for taking the time looking into this.

Re: C# dll import

Richard Andrew x647-Feb-14 9:56

Richard Andrew x64

7-Feb-14 9:56

It's possible that the string being returned is not properly null-terminated.

Or it's possible that the C++ function is returning a locally declared variable, in which case it goes out of scope at the end of the C++ function.

Post the code of the C++ function.

The difficult we do right away...
...the impossible takes slightly longer.

Re: C# dll import

Member 42110407-Feb-14 10:19

Member 4211040

7-Feb-14 10:19

Thanks Richard for your reply.
This is what I thought initially so I made sure that the local string will never go out of scope by declaring it as "static". According to C++ documentations the string::c_str() supposed to return a pointer to null terminated string:
http://www.cplusplus.com/reference/string/string/c_str/[^]

I agree with you, it sound like something happens to the buffer that it becomes no longer valid but I am not sure what happens exactly!.

Re: C# dll import

Richard Andrew x647-Feb-14 12:41

Richard Andrew x64

7-Feb-14 12:41

Member 4211040 wrote:
I agree with you, it sound like something happens to the buffer that it becomes no longer valid but I am not sure what happens exactly!.

Whatever the problem is, I'm sure it is more likely to be on the C++ side than the C# side.

The difficult we do right away...
...the impossible takes slightly longer.

Is it possible to impelement Voice Recognition in C# Web Applicaion?

PALANI KUMAR.A6-Feb-14 22:25

PALANI KUMAR.A

6-Feb-14 22:25

Dear Expertise, I want to implement Voice Recognition in Our Traditional Product. we are using the technology is Visual Studio 2012 (v4.5) with C# web application and SQL server 2012.

Is it possible to impelement Voice Recognition in My Product?

I searched some link like our Code Project and Microsoft sites .. But Max of application using windows based application.
I want to implement using Voice Recognition to open our menu (pages) like Google Voice Recognition

If it is possible means, write suggessted Links for implement it..

Thanks in Advance
Palani Kumar.A
Sundaram Infotech Solutions
Chennai-14

Apkumaar

Re: Is it possible to impelement Voice Recognition in C# Web Applicaion?

Pete O'Hanlon6-Feb-14 23:06

Pete O'Hanlon

6-Feb-14 23:06

The big problem with speech APIs is that there is no one standard mechanism for it. Firefox has its own implementation[^] while Google has a different implementation[^].

Re: Is it possible to impelement Voice Recognition in C# Web Applicaion?

Snehasish_Nandy6-Feb-14 23:06

Snehasish_Nandy

6-Feb-14 23:06