C# Discussion Boards - CodeProject

Re: Customize errors

MihirV22-Jul-05 0:19

MihirV

22-Jul-05 0:19

hi
you have to write two catch Block to handle ODBC and other type of exception..

try<br />
{<br />
//..Code that generate error<br />
}<br />
catch(OdbcException odbc_ex)<br />
{<br />
for (int i=0; i < myException.Errors.Count; i++)<br />
{<br />
if (odbc_ex.Errors[i].NativeError == 42000)<br />
Console.WriteLine("Procedure not found...");<br />
else<br />
Console.WriteLine(odbc_ex.Errors[i].Message);<br />
}<br />
}<br />
catch(Exception ex)<br />
{<br />
//..<br />
}

Mihir...

Re: Customize errors

lovelylooney23-Jul-05 20:09

lovelylooney

23-Jul-05 20:09

Thanks a lot. I will follow what you have said.

Export / Inport of data

nidhelp21-Jul-05 23:21

nidhelp

21-Jul-05 23:21

Hi,
how do i export and import data to a database, thumbdrive, zipdrive etc.. (but first i got to create a database and i dono how to do dat)..

Thz a lot!

passing and recieving specific index of array

iramg21-Jul-05 22:59

iramg

21-Jul-05 22:59

hello
plz tell me how to pass a specific index of the array to a function and how to recieve that what will be function call code and function declaration code.
like if i want to pass array [1] element. so wht will be the passing and receiving code.
thanks

Re: passing and recieving specific index of array

MihirV21-Jul-05 23:20

MihirV

21-Jul-05 23:20

void FunctionCaller()
{
string [] ArrStr = new string[]{"str1","str2","str3"};
int [] ArrInt = new int[]{1,2,3,4,5};
MyFunction(ArrStr[1]);
MyFunction(ArrInt[2]);
}

void MyFunction(object ArrElement)
{
Console.WriteLine(ArrElement);
}

may be helpful to you Smile | :)

Mihir...

Check if a string doesn't starts with a caracter

anderslundsgard21-Jul-05 22:18

anderslundsgard

21-Jul-05 22:18

Well, how would you: check if a string doesn't starts with a caracter.

I've gladly take tips on good string searching/manipulating classes. I'm wellknown of StringBuilder...

_____________________________

...and justice for all

APe

Re: Check if a string doesn't starts with a caracter

AmmuRaj21-Jul-05 22:43

AmmuRaj

21-Jul-05 22:43

U means "string doesn't starts with a character" ?

If so,
if(!strName.StartsWith(ch))

Ammu

Re: Check if a string doesn't starts with a caracter

anderslundsgard21-Jul-05 23:25

anderslundsgard

21-Jul-05 23:25

But I like to check if it starts with a or b or c or.....

Don't really like to do this:

if (str.StartsWith("a")...)....
if (str.StartsWith("b")...)....
if (str.StartsWith("c")...)....
if (str.StartsWith("d")...)....
if (str.StartsWith("e")...)....

_____________________________

...and justice for all

APe

Re: Check if a string doesn't starts with a caracter

lovelylooney21-Jul-05 23:42

lovelylooney

21-Jul-05 23:42

private void txtFirstName_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)

if(txtbox1.Text.Length == 0)
{
if (!Char.IsLetter(e.KeyChar))
e.Handled=true;
}
}

The above code in will check for each key press and will only allow characters...You can modify the code to ur advantage...

Looney

Re: Check if a string doesn't starts with a caracter

AmmuRaj22-Jul-05 1:37

AmmuRaj

22-Jul-05 1:37

So u want to check whether the first character is alphabet or digit. Am I correct ????

Then,

char.IsLetter(str,0)

It will return true if the first character is a letter; otherwise false.

Rose | [Rose]

Ammu

Ammu

Read from a used file.

adonis.damian21-Jul-05 19:53

adonis.damian

21-Jul-05 19:53

Hello,
Using C#, how can I read from a file which is used be another process? Something like Notepad opens a file which is used be another process.

Thank you in advance,

adosun

Re: Read from a used file.

MihirV22-Jul-05 0:06

MihirV

22-Jul-05 0:06

hi
i think it is not possible to access file which is accessed by the another process..you will get access violation exception while accessing this file.

...but in a case, you open a text file in any editor e.g Notepad, WordPad you can access file coz what editor does is it access file and append it in to the control and close it. Smile | :)

Mihir...

Re: Read from a used file.

Dave Kreskowiak22-Jul-05 4:41

Dave Kreskowiak

22-Jul-05 4:41

If the file is opened DenyShareRead by the host process, you can't open it until the host closes the file, period. There's no way around this.

By deault, the FileStream object opens a file with FileShare.Read permissions. That means that any other process can open the file for reading while you have the file open.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

Only one copy of application allowed to run

Anonymous21-Jul-05 19:13

Anonymous

21-Jul-05 19:13

How can I ensure that only one copy of my application (C#) runs?

(In technical terms - it may mean one process or one thread or something else?)

Thanks

Re: Only one copy of application allowed to run

Andrew Kirillov22-Jul-05 0:27

Andrew Kirillov

22-Jul-05 0:27

Don't you like to search here before ?

You can use mutex for it. There are a lot articles on the topic. Here is one of them [^].

Andrew

Re: Only one copy of application allowed to run

MihirV22-Jul-05 0:40

MihirV

22-Jul-05 0:40

hi
do this

public static void Main()<br />
{<br />
<br />
System.Diagnostics.Process[] process = <br />
 System.Diagnostics.Process.GetProcessesByName("YourAppName");<br />
<br />
if ( process.Length >= 2 )<br />
{<br />
MessageBox.Show("Application already running..");<br />
Appliction.End();<br />
}<br />
else<br />
{<br />
Application.Run(new Form1());<br />
}<br />
<br />
}

Mihir...

checking MSWord version

ppp00121-Jul-05 17:59

ppp001

21-Jul-05 17:59

Hi,

How to check the version of MSWord installed in the pc in C# ?
Any code samples ?

Thanks

How to setup a CDECL callback to C# Delagate

Think RS23221-Jul-05 15:01

Think RS232

21-Jul-05 15:01

I have a Win32 DLL that has a standard _stdcall (WINAPI) exports. I am able to call these fine from C#. One call in particular however has a callback to a CDECL function. How would I set that up? Following is the specific.

Win32 DLL Declaration for function in MyDLL.dll
extern "C" int WINAPI SpecialTimerFunction(int Val, int (*Callback)(int InVal))

C# Declaration
public class MyClass
{
public delegate int MyCallback(int InVal);

[DllImport("MyDLL.dll")]
public static extern int SpecialTimerFunction(int Val,MyCallback Callback);
}

How do I declare the delegate to ensure that the marshaller will understand that the callback is of type CDECL?

Thanks a million.
Berto

WCSC (Willies Computer Software Co)
http://www.wcscnet.com

Re: How to setup a CDECL callback to C# Delagate

leppie21-Jul-05 22:01

leppie

21-Jul-05 22:01

Think RS232 wrote:
public delegate int MyCallback(int InVal);

This looks correct.

Define the import function as:
static extern int SpecialTimerFunction(int Val,IntPtr Callback);

When you are creating the delegate wrap it in a GCHandle (pinned). As follows:

GCHandle gch = new GCHandle(new MyCallback(foo), GCHandleType.Pinned);
int res = SpecialTimerFunction(bar, gch.AddressOfPinnedObject());
gch.Free();

^{xacc-ide 0.0.15 now with C#, MSIL, C, XML, ASP.NET, Nemerle, MyXaml and HLSL coloring - Screenshots}

Re: How to setup a CDECL callback to C# Delagate

Think RS23224-Jul-05 3:33

Think RS232

24-Jul-05 3:33

Thanks for the reply.

My concern is that the callback routine in the DLL expects the delagate to be of type CDECL and not _stdcall (WinAPI). Is there some way to specify this?

WCSC (Willies Computer Software Co)
http://www.wcscnet.com

Re: How to setup a CDECL callback to C# Delagate

leppie24-Jul-05 4:21

leppie

24-Jul-05 4:21

a delegate to static method should be fine. if that doesnt work, you can try specify the calling convention on the method, not sure if that will help.

^{xacc-ide 0.0.15 now with C#, MSIL, C, XML, ASP.NET, Nemerle, MyXaml and HLSL coloring - Screenshots}

Finding out if Ctrl key is pressed

Luis Alonso Ramos21-Jul-05 14:49

Luis Alonso Ramos

21-Jul-05 14:49

Hello,

I'm trying to implement multiple sort in a ListView control (yes, it will come later to CP as an article) but I can't find out if the Ctrl key is pressed down when I get the ColumnClick event.

In Win32 there's GetKeyState, but what's the equivalent in .NET? Any ideas?

-- LuisR

Luis Alonso Ramos
Intelectix - Chihuahua, Mexico

Not much here: My CP Blog!

Re: Finding out if Ctrl key is pressed

Mike Dimmick22-Jul-05 0:10

Mike Dimmick

22-Jul-05 0:10

For Ctrl, Alt and/or Shift, you can check the Control.ModifierKeys[^] property.

Otherwise I think you're stuck with P/Invoke on GetKeyState.

Stability. What an interesting concept. -- Chris Maunder

Re: Finding out if Ctrl key is pressed

Luis Alonso Ramos22-Jul-05 6:19

Luis Alonso Ramos

22-Jul-05 6:19

Thanks, that will do it! Smile | :)

-- LuisR

Luis Alonso Ramos
Intelectix - Chihuahua, Mexico

Not much here: My CP Blog!

simultte splitter moving effect

Sasuko21-Jul-05 12:50

Sasuko

21-Jul-05 12:50

If i add to my application a splitter and i try to move, it shows a transparent line following the cursor.
I would simulate this line.
I've to show this line if i click on a panel.
How could i do?

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.