array with keys javascript code example

Example 1: js key value array

var myArray = {id1: 100, id2: 200, "tag with spaces": 300};
myArray.id3 = 400;
myArray["id4"] = 500;

for (var key in myArray) {
  console.log("key " + key + " has value " + myArray[key]);
}

Example 2: array of array key value javascript

var categories = [
    {"1":"Category 1"},
    {"2":"Category 2"},
    {"3":"Category 3"},
    {"4":"Category 4"}
];

Example 3: get keys of an array angualr

for (let obj of arr) {
    console.log("object:", obj);
    for (let key in obj) {
        console.log("      key:", key, "value:", obj[key]);
    }
}