Dynamic variables in JavaScript

1. What is the use of Dynamic variables? Any scenarios?

2. Can I attach this value to a TextField?

   var data = "testVariable";
   eval("var temp_" + data + "=123;");
   alert(temp_testV开发者_如何转开发ariable);
   

What is the use of Dyanmic variables? Any Scenarious

For when people haven't heard of objects or arrays.

Can i attach this value to a TextField?

Yes.

The answer to 2) is 'yes you can'.

However for 1), and overall, you probably shouldn't be using eval: Why is using the JavaScript eval function a bad idea?

As another comment and the currently upvoted answer says - either use arrays or a map.