How to empty INPUT after checking for numeric value?

Question

I would like to check if the INPUT value is a number, and if not, the field should be cleared. The script below always gives the alert if it's not numeric, but never cleares the input. Anyone an idea what I did wrong?

<script>
   function numeric(input)
   {
      if(isNaN(input))
      {
          alert("Is not a numeric value");
          input.value="";
      }
   }
</script>

<input type="number" value="" name="<?php echo $x; ?>" onblur="return numeric(value)"/>

Answer 1

Use this

$( "#numerictext" ).keyup(function() {

var numberRegex = /^[+-]?\d+(\.\d+)?([eE][+-]?\d+)?$/;
var str = $('#numerictext').val();

if(!numberRegex.test(str)) {
   alert("Is not a numeric value");
   $('#numerictext').val('')
}

});

    <input type="number" id="numerictext" value="" name="<?php echo $x; ?>"/>