So I'm just testing something with js, basically the number in the first input has to be bigger than the number in the second input for the submit button to be activated.
The button get's disabled just right, but if I change the number it won't activate again
<!DOCTYPE HTML>
<html>
<body>
<input type='number' id='first' onchange="validateNumber()"/><br>
<input type='number' id='second' onchange="validateNumber()"/><br>
<script type="text/javascript" >
function validateNumber()
{
var first = document.getElementById('first').value;
var second = document.getElementById('second').value;
if(first > second){
document.getElementById('sub').disabled=false;
}else{
document.getElementById('sub').disabled=true;
}
}
</script>
<input type="submit" id="sub"/>
</body>
</html>
Edit: The arrows of the number input trigger onchange it seems, that caused the problem
So I'm just testing something with js, basically the number in the first input has to be bigger than the number in the second input for the submit button to be activated.
The button get's disabled just right, but if I change the number it won't activate again
<!DOCTYPE HTML>
<html>
<body>
<input type='number' id='first' onchange="validateNumber()"/><br>
<input type='number' id='second' onchange="validateNumber()"/><br>
<script type="text/javascript" >
function validateNumber()
{
var first = document.getElementById('first').value;
var second = document.getElementById('second').value;
if(first > second){
document.getElementById('sub').disabled=false;
}else{
document.getElementById('sub').disabled=true;
}
}
</script>
<input type="submit" id="sub"/>
</body>
</html>
Edit: The arrows of the number input trigger onchange it seems, that caused the problem
Share Improve this question edited Nov 12, 2011 at 14:05 deemel asked Nov 12, 2011 at 13:49 deemeldeemel 1,0365 gold badges17 silver badges35 bronze badges3 Answers
Reset to default 7You have to add the onclick and onkeyup event in order to respond to mouse interactions and to inserts from the clipboard:
http://jsfiddle/wzvvN/1
<input type='number' id='first' onkeyup="validateNumber()" onclick="validateNumber()" onchange="validateNumber()" />
<input type='number' id='second' onkeyup="validateNumber()" onclick="validateNumber()" onchange="validateNumber()" />
Try binding the onfocus and onblur events to.
<input type='number' id='first' onchange="validateNumber()" onfocus="validateNumber()" onblur="validateNumber()"/><br>
<input type='number' id='second' onchange="validateNumber()" onfocus="validateNumber()" onblur="validateNumber()"/><br>
You may want to use onkeyup(), since onchange() gets called only when you switch focus to another element.
Also, your function is currently paring strings. Use parseInt to convert to an integer and then pare. The following code works for me:
<html>
<body>
<input type='number' id='first' onkeyup="validateNumber()"/><br>
<input type='number' id='second' onkeyup="validateNumber()"/><br>
<script type="text/javascript" >
function validateNumber()
{
var first = parseInt(document.getElementById('first').value, 10);
var second = parseInt(document.getElementById('second').value, 10);
if(first > second){
document.getElementById('sub').disabled=false;
} else {
document.getElementById('sub').disabled=true;
}
}
</script>
<input type="submit" id="sub" disabled="disabled" />
</body>
</html>