if statement starting to get tricky for me

[Reaper0167]

The code at the bottom of this post works, I would like to also add something like this to it

(document.form2.track.value.lastIndexOf(".rar",".zip")==-1)

The text box id track can only accept a .rar or a .zip,

I'm sure the code above is wrong. Could anyone help me out so that i could add it to the coding below. Thanks.

 

 

if ((!form2.track_name.value) || (!form2.description.value) || (!form2.track.value) || (!form2.image.value) || (document.form2.image.value.lastIndexOf(".jpg")==-1))
{
       	var messID = document.getElementById("flash_vid_table");
	messID.style.display = "none";

}
else
{
    	var messID = document.getElementById("flash_vid_table");
	messID.style.display = "block";
	document.body.style.cursor = 'wait';
}

[Reaper0167]

Sorry if that got confusing. All I'm looking to do is check to see if the extension is a .zip or .rar

 

(document.form2.track.value.lastIndexOf("Check for rar and zip here")==-1)

 

Can this be done with 2 extensions?