[jQuery] How to iterate and manipulate an object

[Pops]

Is this the only way to iterate through an object?

     for ( x in myObject) {
     }

and how can you remove an field in an object?

For example:

   var obj = {
       x1: 1123,
       x2: 212,
       x3: 123131
   };

I want to remove obj.x2 the obj object to end up with:

   { x1: 1123, x3: 123131}

Thanks

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HLS