iterate through a map in javascript

I have a structure like this:

var myMap = {
    partnr1: ['modelA', 'modelB', 'modelC'],
    partnr2: ['modelA', 'modelB', 'modelC']
};

I am going to iterate through each of the elements (partnr) with their associatives (models).

I am trying a double $each iteration in order to achieve this, but nothing happens:

$.each(myMap, function (i, val) {
    $.each(i, function (innerKey, innerValue) {

        setTimeout(function () {
            $('#variant').fadeOut("slow", function () {
                $(this).text(innerKey + "-" + innerValue).fadeIn("slow");

            });

        }, i * 6000);

    });
});

The effect with fading in and out that I am trying to achieve is working fine when using a single value array (Object), but not when I need to have more than one value for each key like here.

Any ideas of how to accomplish this iteration succesfully and are there other ways than using a map that would be better in this case ?

Any suggestions would be of interest.

An answer to your Question from 2019:

It depends on what version of ECMAScript you use.

Pre ES6:

Use any of the answers below, e.g.:

for (var m in myMap){
    for (var i=0;i<myMap[m].length;i++){
    ... do something with myMap[m][i] ...
    }
}

For ES6 (ES 2015):

You should use a Map object, which has the entries() function:

var myMap = new Map();
myMap.set("0", "foo");
myMap.set(1, "bar");
myMap.set({}, "baz");

for (const [key, value] of myMap.entries()) {
  console.log(key, value);
}

For ES8 (ES 2017):

Object.entries() was introduced:

const object = {'a': 1, 'b': 2, 'c' : 3};
for (const [key, value] of Object.entries(object)) {
  console.log(key, value);
}

I'd use standard javascript:

for (var m in myMap){
    for (var i=0;i<myMap[m].length;i++){
    ... do something with myMap[m][i] ...
    }
}

Note the different ways of treating objects and arrays.

Functional Approach for ES6+

If you want to take a more functional approach to iterating over the Map object, you can do something like this

const myMap = new Map() 
myMap.forEach((value, key) => {
    console.log(value, key)
})

iterate through a map in javascript

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