[javascript] JavaScript associative array to JSON

How can I convert a JavaScript associative array into JSON?

I have tried the following:

var AssocArray = new Array();

AssocArray["a"] = "The letter A"

console.log("a = " + AssocArray["a"]);

// result: "a = The letter A"

JSON.stringify(AssocArray);

// result: "[]"

There are no associative arrays in JavaScript. However, there are objects with named properties, so just don't initialise your "array" with new Array, then it becomes a generic object.

I posted a fix for this here

You can use this function to modify JSON.stringify to encode arrays, just post it near the beginning of your script (check the link above for more detail):

// Upgrade for JSON.stringify, updated to allow arrays
(function(){
    // Convert array to object
    var convArrToObj = function(array){
        var thisEleObj = new Object();
        if(typeof array == "object"){
            for(var i in array){
                var thisEle = convArrToObj(array[i]);
                thisEleObj[i] = thisEle;
            }
        }else {
            thisEleObj = array;
        }
        return thisEleObj;
    };
    var oldJSONStringify = JSON.stringify;
    JSON.stringify = function(input){
        if(oldJSONStringify(input) == '[]')
            return oldJSONStringify(convArrToObj(input));
        else
            return oldJSONStringify(input);
    };
})();

You might want to push the object into the array

enter code here

var AssocArray = new Array();

AssocArray.push( "The letter A");

console.log("a = " + AssocArray[0]);

// result: "a = The letter A"

console.log( AssocArray[0]);

JSON.stringify(AssocArray);

Agreed that it is probably best practice to keep Objects as objects and Arrays as arrays. However, if you have an Object with named properties that you are treating as an array, here is how it can be done:

let tempArr = [];
Object.keys(objectArr).forEach( (element) => {
    tempArr.push(objectArr[element]);
});

let json = JSON.stringify(tempArr);