Question

144

Only allow numbers, backspace and delete keys on input text

rated 0 times [ 151] [ 7] / answers: 1 / hits: 15299 / 9 Years ago, mon, april 20, 2015, 12:00:00

I have this input text in a HTML5 page:

<input type=text class=quantity 

onkeypress='return (event.charCode >= 48 && event.charCode <= 57) || event.charCode == 8 || event.charCode == 46' required />

Because I need an input text that does allow only numbers, but I could need also delete a number. When I press backspace or delete nothing happens.

The code above only allows numbers. How can I allow also backspace and delete?

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arthur

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answered 9 Years ago leighamarleem · Accepted Answer

keypress event gives only output of letters code. Use keydown instead.

The keypress event is fired when a key is pressed down and that key normally produces a character value (use input instead).

<input type=text class=quantity 

onkeydown='return (event.which >= 48 && event.which <= 57) 

   || event.which == 8 || event.which == 46' required />

I'm using e.which because keydown produce it but, as the doc says, which is deprecated and key should be used instead ( even if not fully implemented )

Check out the Fiddle and keypress docs