C# .NET - how to make backspace working?

Asked By Priyanka

06-Sep-10 01:01 AM

if (char.IsNumber(e.KeyChar) == false)

e.Handled = true;

i tried the above code on key press event for text box but backspace key is not working in it ... how to make it working?

harsh shah replied to Priyanka

06-Sep-10 01:13 AM

Hi,
try the below code

if (e.KeyChar == '\b')
   {
     e.Handled = false;
   }

let me know

Regards,

Harsh Shah

Priyanka replied to harsh shah

06-Sep-10 01:56 AM

it is not working ...
it also accepts both type of values numeric and char.....

i want that text box donot accept char values but backspace should work in that text box...

harsh shah replied to Priyanka

06-Sep-10 02:05 AM

ok
given code is only for back space.
any way try below code it's accept only numeric and backspace.

if (e.KeyChar == '0' || e.KeyChar == '1' || e.KeyChar == '2' || e.KeyChar == '3' || e.KeyChar == '4' || e.KeyChar == '5' || e.KeyChar == '6' || e.KeyChar == '7' || e.KeyChar == '8' || e.KeyChar == '9' || e.KeyChar == '\b')
    {
     e.Handled = false;
    }
    else
   {
      e.Handled = True;
   }

Regards,

Harsh Shah

George replied to harsh shah

06-Sep-10 02:11 AM

Thanks from bottom of my heart.....

Priyanka replied to harsh shah

06-Sep-10 02:17 AM

Thank you so very much....

Anand Malli replied to Priyanka

06-Sep-10 02:21 AM

Hi Priyanka

I have created one small function for you,its completely different approch,there more then one way with which you can achieve this,i have developed one function which is as follows,just let me know,it is something which you want,just create KeyPress event of your textbox like following

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)

{

int[] numArr = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};

char bckSpace = '\b';

int isInt = 0;

bool blnIsInt = int.TryParse(e.KeyChar.ToString(), out isInt);

e.Handled = (isInt != 0 || e.KeyChar == '\b') ? false : true;

}

i think code is self explanatory,if you have any doubt just let me know

THANKS

Priyanka replied to Anand Malli

06-Sep-10 02:29 AM

Thanks you so very much ... it is working properly......

Anand Malli replied to Priyanka

06-Sep-10 02:44 AM

:)...its always good idea to discover new hacks...isnt it...gr8...

bhagavan replied to Priyanka

22-Jul-11 02:22 AM

if ((e.KeyChar < '0') || (e.KeyChar > '9'))
        {
          if (e.KeyChar != '\b')
          {
            e.Handled = true;
          }

        }

It will work

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