Clear all controls in a ASP.NET page with a Master page

Question

I have a asp.net page which is inherited from a master page .I want to clear all controls in this page .I tried using the bellow method .This is not working if a master page is there. Otherwise its working fine any ideas?

private void ClearControls()
{
    foreach(Control c in Page.Controls)
    {
        foreach (Control ctrl in c.Controls)
        {
            if (ctrl is TextBox)
            {
                ((TextBox)ctrl).Text = string.Empty;
            }
        }
    }
}

Did you mean that you want to clear the TextBoxes in both the Page and its MasterPage, or is it simply not clearing the TextBoxes in your Page when you use a MasterPage with it? — KBoek, Jan 12 '11 at 09:31
This might've to do with where you call ClearControls() from ... — KBoek, Jan 12 '11 at 09:31
Why isn't it working if a MasterPage is there? Whats the exception? What does the quickwatch show about Page.Controls? — citronas, Jan 12 '11 at 09:32
it simply not clearing the TextBoxes in your Page when you use a MasterPage with it.I am not getting any errors — , Jan 12 '11 at 09:33

ogun · Accepted Answer · 2011-01-12T09:46:15.810

6

try this:

public void FindAllTextBox(Control ctrl)
{
    if (ctrl != null)
    {
        foreach (Control c in ctrl.Controls)
        {
            if (c is TextBox)
                ((TextBox)c).Text = string.empty;
            FindAllTextBox(c);
        }
    }
}

Ex.:

Control ctrl = this.FindControl("content");
FindAllTextBox(ctrl);

edited Jan 12 '11 at 09:46

answered Jan 12 '11 at 09:32

ogun

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Compare types directly is bad idea. There are operators `as` and `is` for that. Much faster and more properly – abatishchev Jan 12 '11 at 09:40
you can clear all textboxes with this function... FindAllTextBox(this); – ogun Jan 12 '11 at 09:44
Use operator `as`, instead of `is` and `cast` – abatishchev Jan 12 '11 at 09:50
i think there is no difference between cast and as. – ogun Jan 12 '11 at 10:03

score 2 · Answer 2 · edited Jul 15 '15 at 10:54

2

You should be able to do this with Page.Form.FindControl("ContentPlaceHolder1").Controls:

foreach (Control item in Page.Form.FindControl("ContentPlaceHolder1").Controls)
{
    if (item is TextBox)
    {
        ((TextBox)item).Text = string.Empty;
    }
}

edited Jul 15 '15 at 10:54

Knelis

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answered Jul 15 '15 at 10:03

emrah karaman

91
5

score 1 · Answer 3 · edited Jan 12 '11 at 09:45

1

This is probably because of your controls are inside of another container when you add a master page. Have you tried adding another foreach before if?

private void ClearControls()
{ 
    foreach(Control container in Page.Controls) 
    {  
        foreach (Control c in container.Controls)  
        {     
            foreach (Control ctrl in c.Controls)  
            {     
                if (ctrl is TextBox)        
                {          
                    ((TextBox)ctrl).Text = string.Empty; 
                }   
            }  
        }
    }
}

I wouldn't do it this way though. Sometimes hardcoding is better. This would use a lot of resource when called on a page that contains lots of controls.

edited Jan 12 '11 at 09:45

abatishchev

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answered Jan 12 '11 at 09:44

Pabuc

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Use operator `as`, instead of `is` and `cast` – abatishchev Jan 12 '11 at 09:46
is there any case that this would result in an exception? I guess not. – Pabuc Jan 12 '11 at 09:53
See http://stackoverflow.com/questions/2139798/why-is-the-c-as-operator-so-popular – abatishchev Jan 12 '11 at 09:58
I know the difference between as and is yet control can never be null in this example because of the if check. – Pabuc Jan 12 '11 at 09:59
This is the question of performance. And best practice. You do a superfluous operation. – abatishchev Jan 12 '11 at 10:01
I would NEVER loop through all controls in a page as I stated in my answer. I'm sure that would suck more resource than a few casting. :) – Pabuc Jan 12 '11 at 10:03
Don't hard code! Get recursive instead. See code posted below (or possibly above). – immutabl Jan 12 '11 at 11:22

score 1 · Answer 4 · answered Jan 12 '11 at 11:26

Don't hard code:

//Recursively get all the formControls underneath the current one, be it Page, UserControl or whatever.
public static IEnumerable<Control> GetAllControls(this Control parent)  
{  
    foreach (Control control in parent.Controls)  
    {
        yield return control;  
        foreach (Control descendant in control.GetAllControls())  
        {  
            yield return descendant;  
        }  
    }  
}

Then you can call it in your webform / control:

var formCtls = this.GetAllControls().OfType<TextBox>();
foreach(TextBox txtbx in formCtls)
{
    //do what you gotta do ;)

}

score 0 · Answer 5 · answered May 19 '12 at 17:25

Make a method on your .cs like this:

 //Where "this" is Page.
 ClearInput(this);

 private void ClearInput(Control parent)
 {
     foreach (Control c in parent.Controls)
     {
          if (c.Controls.Count > 0)
                ClearInput(c);
          else
          {
               if (c is TextBox)
                  (c as TextBox).Text = "";

               if (c is CheckBox)
                  (c as CheckBox).Checked = false;

                if (c is DropDownList)
                   (c as DropDownList).SelectedIndex = 1;
           }
       }
   }

wont work if you use this in a control residing on a page that is on master page. — Nitesh, Oct 20 '12 at 10:22

score 0 · Answer 6 · edited Aug 24 '12 at 13:47

        private void EnableControls(Control control)
        {
            var textbox = control as TextBox;
            if (textbox != null)
            {
                textbox.Enabled = true;
            }

            var dropDownList = control as DropDownList;
            if (dropDownList != null)
            {
                dropDownList.Enabled = true;
            }

            var radioButton = control as RadioButton;
            if (radioButton != null)
            {
                radioButton.Enabled = true;
            }

            var checkBox = control as CheckBox;
            if (checkBox != null)
            {
                checkBox.Enabled = true;
            }

            foreach (Control childControl in control.Controls)
            {
                EnableControls(childControl);
            }

        }

Some explanation would have been nice, here, to help someone coming across this post later understand it, and why it might be an answer to the question posed. — Andrew Barber, Sep 28 '12 at 07:40

score 0 · Answer 7 · answered Jan 19 '15 at 12:00

    public void getAllCtl(ControlCollection ctls)
    {

        foreach (Control c in ctls)
        {
            if (c is System.Web.UI.WebControls.TextBox)
            {
                //TextBox tt = c as TextBox;
                ////to do something by using textBox tt.
                ((TextBox)c).Text = string.Empty;
            }
            if (c is System.Web.UI.WebControls.CheckBox)
            {
                ((CheckBox)c).Checked = false;
            }
            if (c is System.Web.UI.WebControls.DropDownList)
            {
                ((DropDownList)c).SelectedIndex = -1;
            }
            if (c.HasControls())
            {
                getAllCtl(c.Controls);

            }
        }

    }

calling in aspx.cs file as

        getAllCtl(this.Form.Controls);

This is OK and tested work for all Master-child page and where ever multiple controls are contains in the page...

score 0 · Answer 8 · answered Jan 12 '11 at 09:39

First, use operator as instead of is and cast:

TextBox tb = ctrl as TextBox;
if (tb != null)
{
    tb.Text = String.Empty;
}

Second, you can use ITextControl instead of TextBox.

And third, try next extension method:

public static IEnumerable<T> GetChildControls(this Control control) where T : Control
{
    var children = (control.Controls != null) ? control.Controls.OfType<T>() : Enumerable.Empty<T>();
    return children.SelectMany(c => GetChildControls(c)).Concat(children);
}

Usage:

foreach (var c in this.Page.Controls.GetChildControls<TextBox>())
{
    c.Text = String.Empty;
}

score 0 · Answer 9 · answered Aug 04 '11 at 17:12

I had the same problem but I think I was making it too hard. I'm using an AJAX UpdatePanel control and I just referenced that instead of going all the way up to the MasterPage. This worked for me.

        foreach (Control c in UpdatePanel1.Controls)
        {
            foreach (Control c1 in c.Controls)
            {
                if (c1 is TextBox)
                {
                    TextBox txtBox = (TextBox)c1;
                    txtBox.Text = "0";
                }
            }
        }

score 0 · Answer 10 · edited Nov 02 '11 at 06:41

0

Just keep the controls in Panel, and try the code below

foreach (Control cntrl in pnl.Controls)//pnl is panel id  
                {  
                    if (cntrl is TextBox)  
                    {  
                        TextBox txtBox = (TextBox)cntrl;  
                        txtBox.Text = " ";  
                    }  
                }

edited Nov 02 '11 at 06:41

Awais Qarni

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answered Nov 02 '11 at 04:32

MuraliKrishna

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2

Clear all controls in a ASP.NET page with a Master page

10 Answers10