Unable to supress keys

sampath kumar

Hi all,

I am using one RichTextBox in C# Windows Application. I need to restrict the user from entering any key from keyboard at certain conditions. so, I wrote the following line of code in keydown event of RichTextBox at .

private void richTextBox1_KeyDown(object sender, KeyEventArgs e)
{
e.SuppressKeyPress = true;
}

This is working fine for English US keyboard. But when i changed my regional settings to Korea and keyboard language to Korean, i can enter the Korean characters (like ?????) even after executing the above statement.

even i have tried with the following code

private void richTextBox1_KeyDown(object sender, KeyEventArgs e)
{
e.SuppressKeyPress = true;
e.Handled = true;
}

but in vain.

Please help.
Thanks in advance. .

3 Replies

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sampath kumar14y ago
I tried with the following :

setting "Readonly" property of the richtextbox to true at selected conditions (where i supposed to suppress the key) and again making the "Readonly" property of the richtextbox to "false" in keyup event.

It meets the requirement. Now, it is working fine.

Thanks for your time.
0
Sam Hobbs14y ago
Have you put a breakpoint in the richTextBox1_KeyDown to determine if it executes for the keys that are not being suppressed? If it is not executed then I assume there is another event that you need to also handle.
0
Vulpes14y ago
Although the MSDN documentation is silent on the matter, KeyEventArgs.SuppressKeyPress doesn't always work even on an English keyboard.

For example, on my machine, it can't stop you entering characters using ALT plus digits from the numeric key pad; try ALT + 156 for instance. So, I'm not altogether surprised that it can't stop Korean characters either.

If you want to disable all key entry, I'd just set the richtextbox's ReadOnly property to true.

If you only want to disable some keys, you could set a form level bool variable in the KeyDown eventhandler if those keys are pressed, and then set e.Handled = true in the KeyPress eventhandler if the bool variable is true.

Check this link for an example of the latter technique:

http://msdn.microsoft.com/en-us/library/system.windows.forms.control.keypress.aspx
0