Question

I’m iterating through this object:

var object = { 
   first : {
      child1 : 'test1',
      child2 : 'test2'
   },

    second : {
       child1 : 'test3',
       child2 : 'test4'
    },

   first : {
      child1 : 'test5',
      child2 : 'test6!'
   }
};

with this:

for(var attribute in object){
    alert(attribute + " : " + object[attribute]);
}

First it seemed that it works, but it iterates only on child objects with unique name, so the first object with: first is skipped.

So what’s the proper solution to iterate through an entire object?

Answer 1

JavaScript objects are associative maps, and cannot have multiple values with the same key (name). Your data cannot have that structure.

Another option might be an array of key-value pairs.

var object = [
   ["first", {
      child1 : 'test1',
      child2 : 'test2'
   }],
   ["second", {
       child1 : 'test3',
       child2 : 'test4'
   }],
   ["first", {
      child1 : 'test5',
      child2 : 'test6!'
   }]
];

var i, attribute, value;
for (i = 0; i < object.length; i++) {
    attribute = object[i][0];
    value = object[i][1];
    alert("" + attribute + " = " + value);
}