I have heard that JavaScript does not support associative arrays. Is it true?
I mean:
assocArray = [
{a: ""},
{b: ""},
{c: ""}
];
How do I get the keys of the above assocArray?
I tried using:
for (each in assocArray) {}
But it gives: 0, 1, 2
You can try with flatMap()
The
flatMap()method first maps each element using a mapping function, then flattens the result into a new array. It is identical to amap()followed by aflat()of depth 1, butflatMap()is often quite useful, as merging both into one method is slightly more efficient.
and Object.keys()
The
Object.keys()method returns an array of a given object's own enumerable property names, in the same order as we get with a normal loop.
var assocArray = [{a : "" },{b : ""},{c : ""}];
var keys = assocArray.flatMap(i => Object.keys(i));
console.log(keys);Try to use the spread operator and the Object.keys method:
let assocArray = [{a : "" },{b : ""},{c : ""}];
let oneObject = Object.assign({}, ...assocArray);
let keys = Object.keys(oneObject);
console.log(keys);If you want to loop through the objects of your array, you can use the following.
for(index in assocArray){
assocArray[index]
}
But, I have the feeling that you should use a dictionary:
assocArray = {a : "" , b : "" , c : "" };
And then, loop through it
for (var key in assocArray) {
// Skip loop if the property is from prototype
if (!assocArray.hasOwnProperty(key)) continue;
var obj = assocArray[key];
}
assocArray = [{a : "" }, {b : ""}, {c : ""}];
for(each in assocArray){
console.log(each); // Each is actually the index
console.log(assocArray[each]); // The item at index 'each'
console.log(Object.keys(assocArray[each])[0]); // The first of the keys of the object at index 'each'
}
assocArray.map(item => Object.keys(item)[0])