try...时间紧,没调试<input type=text name=txt1 onpropertychange="mulIt()">
<input type=text name=txt2 onpropertychange="mulIt()">
<input type=text name=mul><script>
function mulIt()
{
var num1 = parseInt(document.all.txt1.value,10);
var num2 = parseInt(document.all.txt2.value,10);
if(isNaN(num1))
num1 = 0;
if(isNaN(num2))
num2 = 0;
document.all.mul.value = num1*num2;
}
</script>
<input type=text name=txt2 onpropertychange="mulIt()">
<input type=text name=mul><script>
function mulIt()
{
var num1 = parseInt(document.all.txt1.value,10);
var num2 = parseInt(document.all.txt2.value,10);
if(isNaN(num1))
num1 = 0;
if(isNaN(num2))
num2 = 0;
document.all.mul.value = num1*num2;
}
</script>
<input type=text name=text1>
<input type=text name=text2>
<input type=button onclick=alert(parseInt(form1.text1.value)*parseInt(form1.text2.value))>
</form>