Add numbers in JScript

**Frankie902** · Feb 21st, 2001, 06:21 PM

I am VERY VERY NEW to JScript, I am wondering what is wrong with this code to make a 2 number adder:
var a = prompt("First Number:","");
var b = prompt("Second Number:","");
alert (a + " + " + b + " = " + (a + b))

It does everything but it just combines then number, like 2+6=26

HELLP!

**Danial** · Feb 21st, 2001, 08:32 PM

Hi,
Use the ParseInt to convert the string to an integer and then use the eval method.

Code:

var a =  parseInt(prompt("First Number:","")); 
var b =  parseInt(prompt("Second Number:","")); 
alert (a + " + " + b + " = " + eval(a + b));

**Mark Sreeves** · Feb 22nd, 2001, 03:43 AM

...or just use eval()

Code:

var a = eval(prompt("First Number:",""));
var b = eval(prompt("Second Number:",""));
alert (a + " + " + b + " = " + (a + b))

**visordown** · Feb 23rd, 2001, 07:48 AM

Superb ! carrying on from this

if i have 3 text boxes - left,center and right

what would the code be to add left and center values to present the answer in right ?

Any help is appreciated

**Mark Sreeves** · Feb 26th, 2001, 06:48 AM

visordown
This works in IE
I haven't tried it in NS

Code:

<HTML>
<HEAD>
<script language=JavaScript>
function addThem()
{
	document.frm1.txt3.value=eval(document.frm1.txt1.value)+ eval(document.frm1.txt2.value)


}

</script>
</HEAD>
<BODY>
<form name=frm1>
<input name=txt1 size=4 onKeyup="addThem()">
<input name=txt2 size=4 onKeyup="addThem()">
<input name=txt3 size=4>
</form>
</BODY>
</HTML>

**visordown** · Feb 26th, 2001, 07:00 AM

thankyou very much u r far too clever for your own good

cheers a lot pal !

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