C# Discussion Boards - CodeProject

Tomas Brennan17-Sep-04 6:00

17-Sep-04 6:00

Great thanks for your solution, even I changed the event to MouseUp it worked! But nonetheless I'll certainly remember this! Smile | :)

;)

Performance question

BoxenBiene12-Sep-04 4:21

BoxenBiene

12-Sep-04 4:21

Hi all, I'm again,

In my project I want to draw some points with "drawEllipse" dependent on a switch. Now my question:

Is it better to save the points in an Array like "int[] Points1 = new int[5] { 12, 14, 17, 45, 70 }; and then draw the points in a loop or should I draw the points in the switch one after the other with the drawEllipse?

What's with the performance and what's with the resources?

Thanks in advance

BB

switch question

BoxenBiene12-Sep-04 3:37

BoxenBiene

12-Sep-04 3:37

Hi all,

I want to build a switch for the ". How can I do this?

Thanks in advance

BB

Re: switch question

Dennis C. Dietrich12-Sep-04 4:02

Dennis C. Dietrich

12-Sep-04 4:02

You can use characters like double quotes by incorporating the escape character \. See also: .NET Framework General Reference - Character Escapes[^]
If you're switching a string try this:

switch (MyString)
{
  case "\"":
    MessageBox.Show("It's a \"!");
    break;
}

Or rather this example, if you're switching a char:

switch (MyChar)
{
  case '\"':
    MessageBox.Show("It's a \"!");
    break;
}

Best regards
Dennis

Re: switch question

BoxenBiene12-Sep-04 4:26

BoxenBiene

12-Sep-04 4:26

Thanks Dennis, I see I was on the right way but I allway forgot something.

embeding a NumericUpDown column in a datagrid

BaraaSh12-Sep-04 3:30

BaraaSh

12-Sep-04 3:30

Hello

could anyone help me to find a way to embed a numericupdown column in a dataGrid??

thanks..

bhshs

numericupdown column in datagrid

BaraaSh12-Sep-04 3:18

BaraaSh

12-Sep-04 3:18

Hello..

Could anyone help me to find a way to embed a numericupdown column in a datagrid??

thanks..

bhshs

Re: numericupdown column in datagrid

sreejith ss nair12-Sep-04 20:50

sreejith ss nair

12-Sep-04 20:50

hi,
will you please see documentation for
DataViewGrid.

**************************
S r e e j i t h N a i r
**************************

C# send arraylist between forms

Member 119488412-Sep-04 3:15

Member 1194884

12-Sep-04 3:15

I have two forms and form1 call form2 where some data are in arraylist with some struct. How can send the struct with data from Form2 back to 1.

Best Reagrds OMG | :OMG:

Danyboy

Re: C# send arraylist between forms

Nick Parker12-Sep-04 4:35

Nick Parker

12-Sep-04 4:35

You can do this either by making your data structures public or through events and delegates. If you are unfamiliar with events and delegates, Chris Sells wrote a nice articles here: .NET Delegates: A C# Bedtime Story[^].

- Nick Parker
My Blog | My Articles

Re: C# send arraylist between forms

Member 119488412-Sep-04 5:14

Member 1194884

12-Sep-04 5:14

I had implement event to do this but i still have problems. there is any example.

form_1

...
bt_Click(object sender, System.EventArgs e)
{
form2 myform = new form2();
form2.Notify+=new eventHandler(myform2_Notify);
form2.show();
}

myform2_Notify(object sender,EventArgs e)
{
// AS far i undertand here i put the code to //handle the data thats comes form form2 by //"sender"
// I want to receive form form2 the struc Reg
}

.....
form2
public event Eve EventHandler Notify;

protected void OnNotify()
{
if(NotifyDaddy !=null)
//Reg is public struct
NotifyDaddy(Reg,EventArgs.Empty);
}
private void bt2_Click(object sender, System.EventArgs e)
{
this.OnNotifyDaddy();
this.Close();
}

OMG | :OMG:

DanyBoy

Re: C# send arraylist between forms

Nick Parker12-Sep-04 6:18

Nick Parker

12-Sep-04 6:18

Here is a quick example:

public class Form1 : System.Windows.Forms.Form
{
		public delegate void AddDataEventHandler(string s);
		public event AddDataEventHandler DataChanged;

		public void OnDataChanged(string s)
		{
			if(DataChanged != null)
				DataChanged(s);
		}
		
		private void someButton_Click(object sender, EventArgs e)
		{
			Form2 f2 = new Form2();
			this.DataChanged += new AddDataEventHandler(f2.AddData);
			f2.Show();
		}
		
		private void AddData_Click(object sender, EventArgs e)
		{
			string val = this.textBox1.Text;
			if(val != null)
				this.OnDataChanged(val);
		}
}

public class Form2 : System.Windows.Forms.Form
{
		private ListBox listBox1;
		
		public void AddData(string s)
		{
			this.listBox1.Items.Add(s);
		}
}

- Nick Parker
My Blog | My Articles

Re: C# send arraylist between forms

Member 119488412-Sep-04 7:45

Member 1194884

12-Sep-04 7:45

Thanks for your help
I try to adapt for wath I want but only works with a string if a define on delegate

some class src.tools ...
public delegate void test1Event(main1.sub1 Reg);

form1
public event src.tools.teste1Event DataChanged

will not work. Reg.val1 we always =0
if i try to read by Reg.Tostring(); I got "main1.sub1+Reg"

best Regards

OMG | :OMG:

DanyBoy

Re: C# send arraylist between forms

Member 119488412-Sep-04 7:50

Member 1194884

12-Sep-04 7:50

sorry its working Thanks..... Big Grin | :-D

DanyBoy

HC_SKIP

Hadi Fakhreddine12-Sep-04 1:35

Hadi Fakhreddine

12-Sep-04 1:35

Hi,
I'm trying to implement a journal playback proc in C#...the journal record seems to be working fine...however the HC_SKIP in playback proc seems to never get reached...apparently windows keeps calling the playback proc with code HC_GETNEXT only...so i can't advance to the next message until HC_SKIP is called...has anyone ever had this issue?
Thanks

How do you handle inserting " ' " character in program?

ting66812-Sep-04 1:16

ting668

12-Sep-04 1:16

Hi How do you handle inserting " ' " character in program?

e.g

sqlcommand.CommandText = "INSERT INTO Table1 VALUES ('" + value1 + "', '" + value2 + "')";

if value1 is "'" (single quotation), it will cause error. To solve this, it is need to test value1 have got single quotation or not. If yes, insert one more single quotation before the original one. However, I think it is too trouble. Is there any other way to solve it? Thanks!

Re: How do you handle inserting " ' " character in program?

Hadi Fakhreddine12-Sep-04 1:42

Hadi Fakhreddine

12-Sep-04 1:42

You can use the Replace() function.
Use it before executing the sqlcommand:
It is of the form:
Replace(TheString, WhatToReplace, ReplaceItWithWhat)

So apply it this way on all your variables before inserting them into the sqlcommand string:

Replace(value1, "'", "''")
Replace(value2, "'", "''")

Cheers
Cool | :cool:

Re: How do you handle inserting " ' " character in program?

mav.northwind12-Sep-04 1:47

mav.northwind

12-Sep-04 1:47

Hi!
I think you really should use parameterized queries. That way you don't have to worry about such things as how to place your quotes and are less prone to SQL injection attacks.

mav

Illegal Cross Thread Opperation

eggie511-Sep-04 15:37

eggie5

11-Sep-04 15:37

Is there a way to make VS.net 2005 ignore the "Illegal Cross Thread Opperation" in debug mode?

/\ |_ E X E GG

Re: Illegal Cross Thread Opperation

eggie511-Sep-04 17:41

eggie5

11-Sep-04 17:41

Nevermind, this is the solution...

private void button1_Click(object sender, EventArgs e)
{
    Thread nThread = new Thread(delegate()
    {
        int i=0;
        while (i < progressBar1.Maximum)
        {
            progressBar1.Invoke((MethodInvoker)delegate
            {
                progressBar1.Value = i++;
            });
            Thread.Sleep(500);
        }
    });
    nThread.Start();
}

"Reason:
The UI controls are not thread safe. Previous versions of .Net would
allow these thread-unsafe to be made, but they will cause weird things
to happen (often resulting in the application just disappearing)
eventually. .Net 2 detects these bad cross-thread calls, and raises an
exception.

When in another thread, you should invoke all UI control methods using
BeginInvoke and EndInvoke rather than directly."

http://www.dotnet247.com/247reference/msgs/54/272634.aspx[^]

/\ |_ E X E GG

TrackBar in a ToolStrip

eggie511-Sep-04 10:31

eggie5

11-Sep-04 10:31

Does anybody know how to put a trackbar in a toolstrip?

/\ |_ E X E GG

Capturing Window, I got C++ code - please help!

nantcom11-Sep-04 8:21

nantcom

11-Sep-04 8:21

I was looking for a way to capture a window and render it with Direct 3D as my little research on how microsoft create their new hardware accelerated desktop Big Grin | :-D

and i got this from expert exchange

<br />
HDC hdc = GetDC(hwndExplorer);<br />
HDC hdcMem = CreateCompatibleDC(hdc);<br />
RECT r;<br />
GetClientRect(hwndExplorer, &r);<br />
HBITMAP hbm = CreateBitmap(r.right - r.left, r.bottom - r.top, 1, 32, NULL);<br />
HGDIOBJ hbmOld = SelectObject(hdcMem, hbm);<br />
SendMessage(hwndExplorer, WM_PRINT, (WPARAM)hdcMem, PRF_CHILDREN | PRF_CLIENT);<br />

I have tried to convert it (with my little knowledge :S) to this:

<br />
IntPtr victim = API.FindWindow( null, null );<br />
API.GetClientRect( victim, out victimClientArea );<br />
Bitmap b = new Bitmap(  victimClientArea.Width, victimClientArea.Height );<br />
<br />
Graphics gB = Graphics.FromImage( b );<br />
IntPtr hdcB = gB.GetHdc();<br />
<br />
API.SendMessage( victim, (uint)API.WMDefs.WM_PRINT, hdcB, (IntPtr)(API.PRF_CHILDREN | API.PRF_CLIENT | API.PRF_OWNED) );<br />

i got blank bitmap from this code ?
Can anyone help me out!?!?

Re: Capturing Window, I got C++ code - please help!

Nick Parker11-Sep-04 10:05

Nick Parker

11-Sep-04 10:05

Check out the following article here on Code Project: Image Capture[^]

- Nick Parker
My Blog | My Articles

Re: Capturing Window, I got C++ code - please help!

nantcom11-Sep-04 19:20

nantcom

11-Sep-04 19:20

Thanks! The code works, but it require the window you want to capture to be active.
Otherwise, you will get whatever inside the area of that window :S

i change the capture code from:

<br />
GDI32.BitBlt(capHDC,0,0,width,height,wndHDC,x,y,GDI32.SRCCOPY); <br />

to:

<br />
USER32.SendMessage( wndHWND, Constants.WM_PRINT, capHDC, (IntPtr)( Constants.PRF_CHILDREN + Constants.PRF_CLIENT + Constants.PRF_OWNED ) );<br />

and i can capture anything anywhere - even the window is not inside the screen - but the problem is...i can't capture another application's window!!! Confused | :confused:

what happended this time ???
Do i have to get special permission for my application to send messsage to another window?

Found the way!

nantcom11-Sep-04 22:10

nantcom

11-Sep-04 22:10

There is a API called PrintWindow. Big Grin | :-D

<br />
[DllImport("user32.dll", SetLastError=true)]<br />
static extern IntPtr PrintWindow(IntPtr hwnd, IntPtr hDC, uint nFlags);<br />

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