What's wrong with this simple function?

[Wardrop]

Why isn't this doing what I want?

function switchImage(obj) {
	if (obj.src == 'images/minus.gif') {
		obj.src = 'images/plus.gif';
	}
	else {
		obj.src = 'images/minus.gif';
	}
}

basically, this function is meant to check what image is currently set as the source, and swap it with the other image. I'm using it as part of a collapsing tree. What's happening at the moment is it will change the sign from plus.gif to minus.gif (as the if statement returns false so it performs the else command) but the if statement doesn't parse as true even when 'obj' is set to 'images/minus.gif'. I'm a javascript noob, so I could have made a really basic mistake.

I always call the function within an img tag like so onclick="switchImage(this)". Here's the exact img tag I'm using incase that helps.

<img src="images/plus.gif" onclick="switchImage(this);">

Heaps of brownie points to those who help

Cheers!

[Buddy Bradley]

Use alert() to check what the src is set to - it may be that once you've changed it, the obj.src is not exactly equal to that string.

[hexburner]

The obj.src will contain the entire URL to the image, so images/plus.gif would become http://www.mydomain.com/images/plus.gif.

[Logic Ali]

img.src will contain the full path and therefore won't match what you've specified. You need to check for a substring:

function switchImage(obj)
{
 obj.src == obj.src.match("images/minus.gif")?'images/plus.gif':'images/minus.gif';
}

[drimsun]

If possible just check for the filename instead of the path in your conditional statement. That way you don't have to know exactly what the path looks like. You could do this by using regular expressions:

function switchImage(obj) 
{
    re = new RegExp("minus.gif", "i");
    if (re.test(obj.src))
        obj.src = "images/plus.gif";
    else
        obj.src = "images/minus.gif";
}