Textbox scroll to caret

luke

please see code, Im trying to dynamically add three text boxes to a tabpage, i need each texbox to scroll down to the end of the page as text from a pipestream comes in, currently only the last textbox being created will do this so i presume something is being overwrote in memory but im not sure how to do tell each textbox to follow the same routine

SendMessage(pipeTextBox.Handle, WM_VSCROLL, (

IntPtr)SB_BOTTOM, IntPtr.Zero);

5 Replies

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luke15y ago
Hi thanks for replies,

slightly changed approach once each textbox is dynamically created (read in from text file and iterated over) and added to a tab, am now calling an event handler with the following code, again only the textbox in the last tab (last entry read in from text file) will scroll down as text is read in all the others just remain at the top of the page and the scrollbar gets larger and i can scroll to the bottom but it isnt done automatically, is this enough info to give any advice?

private void pipeTextBox_TextChanged(object sender, EventArgs e)Control c = (Control)sender;
{

pipeTextBox.Focus();
pipeTextBox.SelectionStart = pipeTextBox.Text.Length;
pipeTextBox.ScrollToCaret();
}

public void createPipes()
{
foreach (DictionaryEntry de in pipeNames)
{
TabPage tab = new TabPage(de.Value.ToString());
pipeTextBox = new TextBox()
pipeTextBox.Name = de.Value.ToString() +
pipeTextBox.Width = 630;
pipeTextBox.Height = 470;
pipeTextBox.Multiline = true;
pipeTextBox.AcceptsReturn = true;
pipeTextBox.WordWrap = false;
pipeTextBox.ScrollBars = scrollbars.both;
pipeTextBox.ReadOnly = true
pipeTextBox.TextChanged += new System.EventHandler(this.pipeTextBox_TextChanged);
tab.Controls.Add(pipeTextBox);
PipeServer srv = new PipeServer(de.Value.ToString(), _uiSyncContext, ref temp);
pipeServers[de.Value.ToString()] = srv;
Control temp = pipeTextBox;
}
}
} }
Sam Hobbs15y ago
You should avoid use of the Windows API directly, such as sending a message using SendMessage, when there are .Net ways of doing what you need to do. It is difficult to help someone if they don't do things the way we assume they would be done. So in other words, the problem might be the result of something else you are doing that is not done using .Net.

So I hope you try using ScrollToCaret as Javeed suggests and that you will look for functions such as that in .Net that you can use instead of using the Windows API directly.

There are many great reasons to use the Windows API directly but .Net makes it unnecessary for most things.
Javeed M Shaikh15y ago
did you try one of these:

textbox1.ScrollToEnd();

or

textbox1.Select(textbox1.Text.Length, 0);
luke15y ago
Hi thanks for the reply, yeah I understand what scolltocaret should be doing but because you have to setofocus on one of the textboxes this will not work in my application. essentially 3 textboxes are being created dynamically (read in from text file) lets say textbox1 textbox2 textbox3. from the code ive posted only textbox3 will adhere to the scrolldown code that I have posted above, does this explain it at all?
Javeed M Shaikh15y ago
the whole idea os ScrollToCaret is to scroll the contents of the control to the current caret position.

example would be:
TextBox1.SelectedText = TextBox2.Text + "\r\n";
TextBox1.ScrollToCaret();

What is the error you are getting?