Are different jQuery files like classes?

Question

If I have two js files that contain variables with the same name, can I use both of the files at the same time? Would those variables cause conflicts?

Thanks.

Answer 1

As long as they are different files, you're safe. Even a file1.js?4 and file1.js?5 works at the same location...the server might return something different with a different query string.

Example:

 <script type="text/javascript" src="scripts/file1.js?v=5">
 <script type="text/javascript" src="scripts/file1.js?v=6">

They might be 2 complete different files, and if so that's fine, they'll both run. The same name isn't a problem, the same actual file might cause some weird behavior, like event handlers being hooked up and firing twice, etc.

Answer 2

They will not cause a conflict. Obviously they have to be in different locations.

 <script src="scripts1/file.js">

 <script src="scripts2/file.js">

Should be just fine.

Answer 3

Yes, global variables are as their name implies, global. Thus:

//file1.js
x = 10;

//file2.js
alert(x); //will alert 10

As long as both files are included in the same page.

Answer 4

Yes, the variable that is declared afterwards would overwrite the variable that is declared first.

Imagine your external Javascript as just being embedded inside the <script></script> that references it.

So if you had this code (assuming that script1, script2, and script3 are included in that order):

// script1.js

var x = 1;
var y = 2;

// script2.js

var x = 2;

// script3.js

alert(x); // 2

Whereas if script2 and script1 swapped places in their order, script3 would alert "1".