how to give scrolling in textbox?

Question

i have taken a textbox

         <TextBox Height="218" HorizontalAlignment="Stretch" Margin="0,56,0,0" Name="txtBox" VerticalAlignment="Top" TextWrapping="Wrap"
             Text="" GotFocus="txtBox_GotFocus" TextChanged="txtBox_TextChanged" IsTabStop="True" 
             IsEnabled="True" IsHitTestVisible="True" VerticalScrollBarVisibility="Auto" Background="White" FontFamily="Tahoma" />       

Now when i enter lot of text in textbox then text scrolled up automatically. I want to show a scrollbar with which user can surf to the whole text. How to do this.

Answer 1

You could use a simple ScrollViewer, like this:

<ScrollViewer Height="219" VerticalScrollBarVisibility="Auto">
    <TextBox  VerticalAlignment="Top" TextWrapping="Wrap" Height="Auto" HorizontalAlignment="Left" Name="textBox1" Text="TextBox" Width="460">

    </TextBox>
</ScrollViewer>

That's in case the text is entered vertically. You could do the same for horizontal scrolling but this method is not quite reliable due to the fact that it doesn't scroll automatically with the default implementation (like I showed).

Generally, I would simply recommend overriding the template for the default control.

Answer 2

There isn't a simple solution to this problem. Additionally, if you are allowing someone to enter a large amount of text it's possible that as they add more lines you coudl reach the height limit (2048px) imposed on UIElements.

If you need users to be able to enter a large amount of text you should consider putting an Input element inside a WebBrowser control and using that for the field instead.

Answer 3

Two simple steps to go for this:

1. Create TextBox_TextInputStart event handler.
2. assuming your scrollviewer is named as sv and textbox is named as txtbx, add the following lines in the event handler method

 this.sv.UpdateLayout();
 this.sv.ScrollToVerticalOffset(this.txtbx.ActualHeight);