views:

13179

answers:

15

When a C# WinForms text box receives focus, I want to select all the text in the textbox.

To see what I mean, click in your web browser's address bar. See how all text was selected? I want to do that.

FASTEST GUN ALERT: please read the following before answering! Thanks guys. :-)

Calling .SelectAll() during the .Enter or .GotFocus events won't work because if the user clicked the textbox, the caret will be placed where he clicked, thus deselecting all text.

Also, calling .SelectAll() during the .Click event won't work because the user won't be able to select any text with the mouse; the .SelectAll() call will keep overwriting the user's text selection. )

+3  A: 

Click event of textbox? Or even MouseCaptureChanged event works for me. - OK. doesn't work.

So you have to do 2 things:

private bool f = false;

private void textBox_MouseClick(object sender, MouseEventArgs e)
{ 
  if (this.f) { this.textBox.SelectAll(); }
  this.f = false;
}

private void textBox_Enter(object sender, EventArgs e)
{
  this.f = true;
  this.textBox.SelectAll();
}
private void textBox_MouseMove(object sender, MouseEventArgs e) // idea from the other answer
{
  this.f = false; 
}

Works for tabbing (through textBoxes to the one) as well - call SelectAll() in Enter just in case...

Jakub Kotrla
Ok Jakub, that partially works. If I tab to the text box, it needs to focus. Will that work with your solution? (If you can show me how, I'll mark your answer as the correct answer.)
Judah Himango
Jakub, now that you've posted the code, it seems to *sometimes* work. Not always; right now I'm clicking into the text box and it's not selecting all.
Judah Himango
Could you describe when it doesn't work?
Jakub Kotrla
Sometimes I'll click into the text and it doesn't select all. It's like somehow the .f field isn't set to what it should be, and then SelectAll doesn't get called. Haven't seen this?
Judah Himango
I know only that because of mouseMouve you can slow-click while move mouse (especially on wide letters) -> unset the flag.You can remove the code in mouseMove event, but than you get- after tabbgin to control and then clicking - reSelectAll- unable to select part of stirng on first drag
Jakub Kotrla
+3  A: 

It's a bit kludgey, but in your click event, use SendKeys.Send( "{HOME}+{END}" );

Todd Benning
Woofta! That is a bit of hackery! :-) Thanks for the suggestion. Any better ideas?
Judah Himango
Hacking indeed, but this doesn't sound bad at all
djerry
Consider that a lot of anti-virus programs intercept and block SEND KEYS as malicious. It's not a great solution.
Judah Himango
+1  A: 
'Inside the Enter event
TextBox1.SelectAll();

Ok, after trying it here is what you want:

  • On the Enter event start a flag that states that you have been in the enter event
  • On the Click event, if you set the flag, call .SelectAll() and reset the flag.
  • On the MouseMove event, set the entered flag to false, which will allow you to click highlight without having to enter the textbox first.

This selected all the text on entry, but allowed me to highlight part of the text afterwards, or allow you to highlight on the first click.

By request:

    bool entered = false;
    private void textBox1_Enter(object sender, EventArgs e)
    {
        entered = true;
        textBox1.SelectAll();   //From Jakub's answer.
    }

    private void textBox1_Click(object sender, EventArgs e)
    {
        if (entered) textBox1.SelectAll();
        entered = false;
    }

    private void textBox1_MouseMove(object sender, MouseEventArgs e)
    {
        if (entered) entered = false;
    }

For me, the tabbing into the control selects all the text.

MagicKat
Your solution is similar to Jakub's solution. It works for clicking. Can it work when tabbing to the text box? (E.g. tabbing to your browser's address bar will select all text too.)
Judah Himango
Yes it works for tabbing too. I wrote a test app and this is the way that I got it working.
MagicKat
Doesn't seem to work for tabbing. Can you show us the code that's working for tabbing?
Judah Himango
A: 
private bool _isSelected = false;
private void textBox_Validated(object sender, EventArgs e)
{
    _isSelected = false;
}

private void textBox_MouseClick(object sender, MouseEventArgs e)
{
    SelectAllText(textBox);
}

private void textBox_Enter(object sender, EventArgs e)
{
    SelectAllText(textBox);
}

private void SelectAllText(TextBox text)
{
    if (!_isSelected)
    {
        _isSelected = true;
        textBox.SelectAll();
    }
}
Nescio
I just tested with a RichTextBox. Doesn't work. Clicking into the textbox doesn't appear to select all text. (Because it's getting deselected on mouse down, when the caret is placed at the cursor.)
Judah Himango
A: 

The below seems to work. The enter event handles the tabbing to the control and the MouseDown works when the control is clicked.

    private void textBox1_Enter(object sender, EventArgs e)
    {
        textBox1.SelectAll();
    }

    private void textBox1_MouseDown(object sender, MouseEventArgs e)
    {
        if (textBox1.Focused)
            textBox1.SelectAll();
    }
benPearce
No luck, doesn't work I'm afraid. Try selecting some text. The .SelectAll text overwrites what the user is trying to select.
Judah Himango
A: 

Interestingly, a ComboBox with DropDownStyle=Simple has pretty much exactly the behaviour you are looking for, I think.

(If you reduce the height of the control to not show the list - and then by a couple of pixels more - there's no effective difference between the ComboBox and the TextBox.)

Interesting, but I really need this to work on TextBox and RichTextBox.
Judah Himango
A: 

Actually GotFocus is the right event (message really) that you are interested in, since no matter how you get to the control you’ll get this even eventually. The question is when do you call SelectAll().

Try this:

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
        this.textBox1.GotFocus += new EventHandler(textBox1_GotFocus);
    }

    private delegate void SelectAllDelegate();    
    private IAsyncResult _selectAllar = null; //So we can clean up afterwards.

    //Catch the input focus event
    void textBox1_GotFocus(object sender, EventArgs e)
    {
        //We could have gotten here many ways (including mouse click)
        //so there could be other messages queued up already that might change the selection.
        //Don't call SelectAll here, since it might get undone by things such as positioning the cursor.
        //Instead use BeginInvoke on the form to queue up a message
        //to select all the text after everything caused by the current event is processed.
        this._selectAllar = this.BeginInvoke(new SelectAllDelegate(this._SelectAll));
    }

    private void _SelectAll()
    {
        //Clean-up the BeginInvoke
        if (this._selectAllar != null)
        {
            this.EndInvoke(this._selectAllar);
        }
        //Now select everything.
        this.textBox1.SelectAll();
    }
}
Ali, this doesn't work. Try mousing down in the middle of the text. Hold down the mouse button for 1 second.
Judah Himango
+16  A: 

Hi guys,

First of all, thanks for answers! 9 total answers. Thank you.

Bad news: all of the answers had some quirks or didn't work quite right (or at all). I've added a comment to each of your posts.

Good news: I've found a way to make it work. This solution is pretty straightforward and seems to work in all the scenarios (mousing down, selecting text, tabbing focus, etc.)

bool alreadyFocused;

...

textBox1.GotFocus += textBox1_GotFocus;
textBox1.MouseUp += textBox1_MouseUp;
textBox1.Leave += textBox1_Leave;

...

void textBox1_Leave(object sender, EventArgs e)
{
    alreadyFocused = false;
}


void textBox1_GotFocus(object sender, EventArgs e)
{
    // Select all text only if the mouse isn't down.
    // This makes tabbing to the textbox give focus.
    if (MouseButtons == MouseButtons.None)
    {
        this.textBox1.SelectAll();
        alreadyFocused = true;
    }
}

void textBox1_MouseUp(object sender, MouseEventArgs e)
{
    // Web browsers like Google Chrome select the text on mouse up.
    // They only do it if the textbox isn't already focused,
    // and if the user hasn't selected all text.
    if (!alreadyFocused && this.textBox1.SelectionLength == 0)
    {
        alreadyFocused = true;
        this.textBox1.SelectAll();
    }
}

As far as I can tell, this causes a textbox to behave exactly like a web browser's address bar.

Hopefully this helps the next guy who tries to solve this deceptively simple problem.

Thanks again, guys, for all your answers that helped lead me towards the correct path.

Judah Himango
Thanks for this! I can't believe it's so hard to do something that should be so simple.You're missing one tiny piece in your solution, though: In GotFocus, after calling SelectAll(), you must set alreadyFocused to True. Otherwise, if you tab into the control (text gets selected) and you want to select a specific part with your mouse, when you click with the mouse it gets all selected again, requiring an extra click. Just my 2 cents.
Daniel Magliola
Ok, added to the source. Thanks Daniel.
Judah Himango
I'm not 100% sure you need the bool alreadyFocused flag. Replacing "!alreadyFocused" in your MouseUp event handler with "!textBox1.Focused" worked fine for me and let me get rid of the Leave event handler entirely. Otherwise, your solution was very helpful.
alabamasucks
hye alabamasucks... i tried as u said n replaced with textbox1.focused. but it didn't worked to me... on mouse up event it doesn't selects the text at all
KoolKabin
A: 

Why don't you simply use the MouseDown-Event of the text box? It works fine for me and doesn't need an additional boolean. Very clean and simple, eg.:

private void textbox_MouseDown(object sender, MouseEventArgs e) {
    if (textbox != null && !string.IsNullOrEmpty(textbox.Text))
    {
        textbox.SelectAll();
    } }
Nope, couple problems with this: doesn't account for if the textbox already has focus (we don't want to select-all every mouse down, just when the textbox didn't have focus), doesn't let you select just a portion of the text, doesn't work when bring focus via tabbing to the textbox.
Judah Himango
A: 

Have you tried the solution suggested on the MSDN Forum "Windows Forms General" which simply subclasses TextBox?

huseyint
I believe we tried that. However, I don't recall the shortcoming with that solution.
Judah Himango
A: 

A one line answer that I use...you might be kicking yourself...

In the Enter Event:

txtFilter.BeginInvoke(new MethodInvoker( txtFilter.SelectAll));

Nope, doesn't work. It selects all text, alright, but it also prevents the user from selecting just part of the text, among other problems.
Judah Himango
Sorry, I must have misunderstood the behavior you were looking for. On enter it selects all, if you click and hold it select from beginning to your cursor. I suppose you could use what I have and replace SelectAll with your own select logic.http://www.notifywire.com/demos/2009-04-14_1248.swf
A: 

I called SelectAll inside MouseUp event and it worked fine for me.

    private bool _tailTextBoxFirstClick = false;

    private void textBox1_MouseUp(object sender, MouseEventArgs e)
    {
        if(_textBoxFirstClick)           
            textBox1.SelectAll();

        _textBoxFirstClick = false;
    }  

    private void textBox1_Leave(object sender, EventArgs e)
    {
        _textBoxFirstClick = true;
        textBox1.Select(0, 0);
    }
Sreejith K.
Yeah, see the other answers (and comments) for why this doesn't work in all scenarios.
Judah Himango
I did not check for tab for this solution. My bad. Thanks for pointing out. Glad to see that you have the complete solution now. And also glad to know that my suggestion for MouseUp was included in your solution.
Sreejith K.
A: 

Just derive a class from TextBox or MaskedTextBox:

public class SMaskedTextBox : MaskedTextBox
{
    protected override void OnGotFocus(EventArgs e)
    {
        base.OnGotFocus(e);
        this.SelectAll();
    }
}

And use it on your forms.

Mohammad Mahdipour
This doesn't work. To understand why, see the other answers and comments.
Judah Himango
A: 

I created a new VB.Net Wpf project. I created one TextBox and used the following for the codebehind:

Class MainWindow 

Sub New()

    ' This call is required by the designer.
    InitializeComponent()

    ' Add any initialization after the InitializeComponent() call.
    AddHandler PreviewMouseLeftButtonDown, New MouseButtonEventHandler(AddressOf SelectivelyIgnoreMouseButton)
    AddHandler GotKeyboardFocus, New KeyboardFocusChangedEventHandler(AddressOf SelectAllText)
    AddHandler MouseDoubleClick, New MouseButtonEventHandler(AddressOf SelectAllText)
End Sub

Private Shared Sub SelectivelyIgnoreMouseButton(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
    ' Find the TextBox
    Dim parent As DependencyObject = TryCast(e.OriginalSource, UIElement)
    While parent IsNot Nothing AndAlso Not (TypeOf parent Is TextBox)
        parent = VisualTreeHelper.GetParent(parent)
    End While

    If parent IsNot Nothing Then
        Dim textBox As Object = DirectCast(parent, TextBox)
        If Not textBox.IsKeyboardFocusWithin Then
            ' If the text box is not yet focussed, give it the focus and
            ' stop further processing of this click event.
            textBox.Focus()
            e.Handled = True
        End If
    End If
End Sub

Private Shared Sub SelectAllText(ByVal sender As Object, ByVal e As RoutedEventArgs)
    Dim textBox As Object = TryCast(e.OriginalSource, TextBox)
    If textBox IsNot Nothing Then
        textBox.SelectAll()
    End If
End Sub

End Class

BSalita
+3  A: 

Your solution is good, but fails in one specific case. If you give the TextBox focus by selecting a range of text instead of just clicking, the alreadyFocussed flag doesn't get set to true, so when you click in the TextBox a second time, all the text gets selected.

Here is my version of the solution. I've also put the code into a class which inherits TextBox, so the logic is nicely hidden away.

public class MyTextBox : System.Windows.Forms.TextBox
{
    private bool _focused;

    protected override void OnEnter(EventArgs e)
    {
        base.OnEnter(e);
        if (MouseButtons == MouseButtons.None)
        {
            SelectAll();
            _focused = true;
        }
    }

    protected override void OnLeave(EventArgs e)
    {
        base.OnLeave(e);
        _focused = false;
    }

    protected override void OnMouseUp(MouseEventArgs mevent)
    {
        base.OnMouseUp(mevent);
        if (!_focused)
        {
            if (SelectionLength == 0)
                SelectAll();
            _focused = true;
        }
    }
}
nzhenry