Add dynamic key, value pairs to JavaScript array or hash table

Question

I'm trying to add a key value pair to an existing javascript associative array. The key needs to be a variable. This is for JSON encoding. I realize there are many plugins and frameworks for this, but I want a simple answer.

ary.push({name: val}); 

where ary is a new array, name is a variable containing the key, val is the value of this entry.

I'm doing this in a jQuery loop that iterates through form fields.

Answer 1

In ES6...

In ES6, you can use a destructuring assignment;

ary.push({[name]: val}); 

However, given this is ES6 syntax, the usual caveats apply; this will not work in some browsers (noticably, IE and Edge 13)... although Babel will transpile this for you.

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Without ES6 (legacy browser support)...

You need to define an object and use square bracket notation to set the property;

var obj = {};  obj[name] = val;  ary.push(obj); 

If you get the urge to read into it more, see this article on the differences between square bracket and dot notation.

Answer 2

var ary = [];  function pushToAry(name, val) {    var obj = {};    obj[name] = val;    ary.push(obj); }  pushToAry("myName", "myVal"); 

Having just fully read your question though, all you need is the following

$(your collection of form els).serializeArray(); 

Good old jQuery