Hmm.. does anyone have a working example of using the message EM_GETLINEfrom C# using SendMessage ? I found its code is 0x00C4.
I just cant get it working right.. I know the first char of the wParam should hold the capacity of the buffer andlParam should be the row number..but I just cant get it right ..

Thanks! :)

I agree, why not use Lines[] instead?

// Get the first line of multi-line textBox1 string line1 = textBox1.Lines[0]; MessageBox.Show(line1);

It's easier that way. But if you insists on using API to send EM_GETLINE message to your multi-line textbox, then you need to modify your API declaration for SendMessage API and make its lParam as StringBuilder type, like this:

[DllImport("user32.dll", EntryPoint="SendMessageA")] private static extern int SendMessage_Ex  (IntPtr hwnd, int wMsg, int wParam, StringBuilder lParam); private const int EM_GETLINE = 0xc4;

Then call it this way:

StringBuilder buffer = new StringBuilder(256); SendMessage_Ex(textBox1.Handle, EM_GETLINE, 0, buffer); MessageBox.Show(buffer.ToString());

Hope this helps,

-chris

Why not use TextBox.Lines?

I agree, why not use Lines[] instead?

// Get the first line of multi-line textBox1 string line1 = textBox1.Lines[0]; MessageBox.Show(line1);

It's easier that way. But if you insists on using API to send EM_GETLINE message to your multi-line textbox, then you need to modify your API declaration for SendMessage API and make its lParam as StringBuilder type, like this:

[DllImport("user32.dll", EntryPoint="SendMessageA")] private static extern int SendMessage_Ex  (IntPtr hwnd, int wMsg, int wParam, StringBuilder lParam); private const int EM_GETLINE = 0xc4;

Then call it this way:

StringBuilder buffer = new StringBuilder(256); SendMessage_Ex(textBox1.Handle, EM_GETLINE, 0, buffer); MessageBox.Show(buffer.ToString());

Hope this helps,

-chris

Thanks, I see now where was my problem .. I added ref keyword to an already referenced type StringBuilder ... And had unbalance error ..
Thanks Again !