How to clear the text of all textBoxes in the form?

private void CleanForm()
{
    foreach (var c in this.Controls)
    {
        if (c is TextBox)
        {
            ((TextBox)c).Text = String.Empty;
        }
    }
}

This method above doesn't work and开发者_如何学编程 the controls aren't cleared. It compiles fine, but does nothing.

Any ideas?

I like lambda :)

 private void ClearTextBoxes()
 {
     Action<Control.ControlCollection> func = null;

     func = (controls) =>
         {
             foreach (Control control in controls)
                 if (control is TextBox)
                     (control as TextBox).Clear();
                 else
                     func(control.Controls);
         };

     func(Controls);
 }

Good luck!

We had a problem like this some weeks before. If you set a breakpoint and have a deep look into this.Controls, the problem reveals it's nature: you have to recurse through all child controls.

The code could look like this:

private void CleanForm()
{
    traverseControlsAndSetTextEmpty(this);
}
private void traverseControlsAndSetTextEmpty(Control control)
{

    foreach(var c in control.Controls)
    {
        if (c is TextBox) ((TextBox)c).Text = String.Empty;
        traverseControlsAndSetTextEmpty(c);
    }
}

private void CleanForm(Control ctrl)
{
    foreach (var c in ctrl.Controls)
    {
        if (c is TextBox)
        {
            ((TextBox)c).Text = String.Empty;
        }

        if( c.Controls.Count > 0)
        {
           CleanForm(c);
        }
    }
}

When you initially call ClearForm, pass in this, or Page (I assume that is what 'this' is).

Your textboxes are probably inside of panels or other containers, and not directly inside the form.

You need to recursively traverse the Controls collection of every child control.

I improved/fixed my extension method.

public  static class ControlsExtensions
{
    public static void ClearControls(this Control frm)
    {
        foreach (Control control in frm.Controls)
        {
            if (control is TextBox)
            {
                control.ResetText();
            }

            if (control.Controls.Count > 0)
            {
                control.ClearControls();
            }
        }
    }
}

And this for clearing all controls in form like textbox, checkbox, radioButton

you can add different types you want..

private void ClearTextBoxes(Control control)
    {
        foreach (Control c in control.Controls)
        {
            if (c is TextBox)
            {
                ((TextBox)c).Clear();
            }

            if (c.HasChildren)
            {
                ClearTextBoxes(c);
            }


            if (c is CheckBox)
            {

                ((CheckBox)c).Checked = false;
            }

            if (c is RadioButton)
            {
                ((RadioButton)c).Checked = false;
            }
        }
    }

Maybe you want more simple and short approach. This will clear all TextBoxes too. (Except TextBoxes inside Panel or GroupBox).

 foreach (TextBox textBox in Controls.OfType<TextBox>())
    textBox.Text = "";

Since none of the answers here helped me, I'm posting the solution that worked for me.

This is applicable when you have textboxes within groupboxes, so you cannot operate using a basic this.Control

you will need to create a double foreach secuence that loops into each groupbox looking for textboxes.

try using this:

public void CleanTxTBoxes()
    {
        foreach (var groupbox in this.Controls.OfType<GroupBox>())
        {
            foreach (var textboxitem in groupbox.Controls.OfType<TextBox>())
            {
                textboxitem.Clear();
            }
        }
    }

You can try this code

protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
    {


        if(keyData==Keys.C)
        {
            RefreshControl();
            return true;
        }


        return base.ProcessCmdKey(ref msg, keyData);
    }

Try this:

var t = this.Controls.OfType<TextBox>().AsEnumerable<TextBox>();
foreach (TextBox item in t)
{
    item.Text = "";
}