document.form[0] does not work on Firefox

Question

function func(){
    with (document.forms[0]){
        inputid.value = "text"; //Works!
        spanid.innerHTML = "text"; //Err, spanid is not defined.
    }
}

This is not working in Firefox but it is in IE7. I debug in Firebug, spanid is not defined, but I can use document.getElementById("spanid") to select this element. I just don't know why? The input element works fine!

At what point are you calling it? It may not be initializing. — orkutWasNotSoBad, Jul 01 '11 at 16:15
I wouldn't be, since I use the inputid and spanid in the same function. The inputid works but the spanid does not. — etlds, Jul 01 '11 at 16:18
That's not even valid syntax, and what does spanid have to do with document.forms[0]? — MooGoo, Jul 01 '11 at 16:36

James Hill · Accepted Answer · 2011-07-01T16:48:22.543

3

Shouldn't it be document.forms[0] (notice the s on form)

**EDIT**

Since the answers aren't rolling in on this one, here's my suggestion. Simply it. Use the methods you're familiar with and don't waste time trying to get this to work.

function YourFunction()
{
    var objSpan = document.getElementById([Insert Element ID]);
    var objInput = document.getElementById([Insert Element ID]);

    objSpan.InnerHTML = "text";
    ...
}

edited Jul 01 '11 at 16:48

answered Jul 01 '11 at 16:18

James Hill

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I think that is why people don't suggest with() – etlds Jul 01 '11 at 16:50
1

@Desheng there are very few real needs for `with`. See http://stackoverflow.com/questions/61552/are-there-legitimate-uses-for-javascripts-with-statement – Matt Ball Jul 01 '11 at 17:12

score 0 · Answer 2 · answered Jul 01 '11 at 20:12

0

IE sticks all elements with IDs as properties on the global scope. Firefox does not do that in standards mode (but does in quirks mode).

answered Jul 01 '11 at 20:12

Boris Zbarsky

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@Quentin Yes, but `document.forms[0]` doesn't get random divs hanging off it. Only some HTML elements end up with their id/name as properties on a `
`, and `
` is not in that set.
– Boris Zbarsky Jul 02 '11 at 00:52

document.form[0] does not work on Firefox

2 Answers2