javascript - For Loop repeats first loop twice - Stack Overflow

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I have this for loop, and it seems to be repeating the first loop twice (x=0) and then not doing the last one (x=2)

for (x=0;x<=2;x++)
    {
        if (document.getElementById("sub"+catCount+x).value != "")
        {
            if (nonums.test(document.getElementById("sub"+catCount+x).value))
            {
                total = total + parseFloat(document.getElementById("sub"+catCount+x).value);
            }
        }
        alert(x);
    }

In other words, I get two alert boxes with "0" in them, then one with "1" in it, and that's it.

Can anyone tell me what I'm not seeing here? Why doesn't it just progress through the loop normally (0,1,2)?

I have this for loop, and it seems to be repeating the first loop twice (x=0) and then not doing the last one (x=2)

for (x=0;x<=2;x++)
    {
        if (document.getElementById("sub"+catCount+x).value != "")
        {
            if (nonums.test(document.getElementById("sub"+catCount+x).value))
            {
                total = total + parseFloat(document.getElementById("sub"+catCount+x).value);
            }
        }
        alert(x);
    }

In other words, I get two alert boxes with "0" in them, then one with "1" in it, and that's it.

Can anyone tell me what I'm not seeing here? Why doesn't it just progress through the loop normally (0,1,2)?

• javascript
• loops

Share Improve this question Follow asked Jun 25, 2010 at 21:48 JimmyJimmy 2,92566 gold badges4545 silver badges5757 bronze badges 6

• 3 Given that x is (possibly) declared as a global, does anything else in the functions you have called alter it? – Yacoby Commented Jun 25, 2010 at 21:50
• 2 This part of the code is not causing the problem. Can you point us to a URL of the whole site? – phihag Commented Jun 25, 2010 at 21:52
• that is literally the only spot I use the variable x on any page. – Jimmy Commented Jun 25, 2010 at 21:53
• @phihag: I can't, really. I'd need to give you a login. – Jimmy Commented Jun 25, 2010 at 21:55
• what happens if you change the variable name? – Dr. belisarius Commented Jun 25, 2010 at 22:03

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2 Answers 2

Sorted by: Reset to default 2

that is literally the only spot I use the variable x on any page.

It works for me.

for (x=0;x<=2;x++)
{
  alert(x);
}

You can test it at console.

I don't think you want the variable x to be global in scope. Try it with the "var" keyword:

for (var x=0;x<=2;x++)
...

I can paste this in my address bar and it will produce 0, 1, 2.

javascript:for (var x=0;x<=2;x++) {alert(x);}

I tried it in IE, FF and Chrome.

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