clearing the C# form contorls

Question

0.00/5 (No votes)

See more:

I've created a form using C# form application.

How to clear the controls like radio buttons, combo boxes along with text boxes when pressing the RESET button.

Posted 25-Dec-11 3:28am

nischalinn

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

#realJSOP · Accepted Answer · 2011-12-25T03:36:00

Solution 1

Radio buttons should ALWAYS have at least one in a given group checked. Otherwise, the data is invalid.

To answer your question, just enumerate your controls and clear the contents.

C#

private void ClearControls(Control ctrl)
{
    if (ctrl.IsContainer)
    {
        foreach (Control child in ctrl.Children)
        {
            ClearControls(child);
        }
    }
    else
    {
        if (ctrl is TextBox)
        {
            ((TextBox)ctrl).Text = "";
        }
        else if (ctrl is CheckBox)
        {
            ((CheckBox)ctrl).Checked = false;
        }
        else if (ctrl is RadioButton)
        {
            ((RadioButton)ctrl).Checked = false;
        }
    }
}

Posted 25-Dec-11 3:36am

#realJSOP

Updated 25-Dec-11 4:01am

v2

Comments

Dalek Dave 25-Dec-11 9:55am

5 from me John, that's how I would do it.
(And good point about the Radio Button).

Sergey Alexandrovich Kryukov 25-Dec-11 12:58pm

Good points, my 5, credited in my answer.
--SA

theanil 25-Dec-11 13:14pm

My 5+

nischalinn 25-Dec-11 21:37pm

Thanks for the solution.
Will you please explain me the code:
private void ClearControls(Control ctrl)
{
if (ctrl.IsContainer)
{
foreach (Control child in ctrl.Children)
{
ClearControls(child);
}
}

#realJSOP 26-Dec-11 6:21am

The method is recursive and accepts any control. When it encounters a container control (like a GroupBox, or a Panel), the method calls itself and the child controls within the container control are enumerated. This allows you to enumerate ALL controls on the form with a single method. Google "recursion" for more complete descriptions of the paradigm). By the way, if I provided the correct answer, make sure you "accept" the solution (and you can accept more than one if it's appropriate).

Espen Harlinn 31-Dec-11 8:27am

Good reply, John :)

Sergey Alexandrovich Kryukov · Accepted Answer · 2011-12-25T06:57:00

There is no a strict sense to be attributed to the term "clear" when it comes to a whole set of all controls. It makes no general sense because controls are not necessarily independent, at least one radio button in a group, as John correctly pointed out, should be checked, etc.

But in many cases, you really need some method of putting all the controls in some initial state. Normally, you call it before a form is shown. If you want to call it again, you can also call it in your "Reset" buttons. (This looks a bit strange though; the usual name for it is called "Defaults" or something like that.) In most cases this is not needed, but I presume you have some reasons to do it.

I just want to point out, that in any more or less complex application such function should be semantic and specific to your application. Here is why: you usually need to separate your UI from a data layer. In this case, you have some data model which populates UI and is modified when a user edits anything (just modifies) using the UI. This way, you have a uniform throughout the application, semantic methods of population and data update. In this approach, the setting up of initial UI state is no different: you have an initial-state instance of data and your "reset" is the population of the UI from this initial instance of the data model.

If you follow this simple approach, you can avoid doing the same thing in different ways and thus avoid many mistakes. After all, always remember one of the most important principles: Don't Repeat Yourself (DRY), see http://en.wikipedia.org/wiki/Don%27t_repeat_yourself[^].

—SA