onclick increment number

Question

With JavaScript, how can I do it so when I click a form button it adds 1 to a number? The number it increments could be in a form text field or something.

Obviously it'd be on onclick but I'm not sure of the code.

Answer 1

Since you gave me nothing to start on, here is a simple example.

jsFiddle

Example implementation:

function incrementValue()
{
    var value = parseInt(document.getElementById('number').value, 10);
    value = isNaN(value) ? 0 : value;
    value++;
    document.getElementById('number').value = value;
}

Example Html

<form>
   <input type="text" id="number" value="0"/>
   <input type="button" onclick="incrementValue()" value="Increment Value" />
</form>