Question

My HTML code is:

<input onKeyPress="validateA(this.value)" type="text" id="AAA" name="AAA" size="10" placeholder="A">
<span id="aspan" class="validate">  </span>

and my Javascript is:

function validateA(valueOfAAA) {
if (isNaN(valueOfAAA)) {
    document.getElementById('aspan').innerHTML="Please enter a numerical value.";

}
else {
    document.getElementById('aspan').innerHTML="";
}

}

To clarify, my question is:

Why is the innerHTML="Please enter a numerical value." not firing until two letters OR numbers are typed into my input box?

Answer 1

change onKeyPress() to onKeyUp()
because when keypress triggered, the actual value of input is not captured yet.