Jquery how to find an Object by attribute in an Array

Question

Given I have an array of "purpose" objects:

//array of purpose objects: var purposeObjects = [     {purpose: "daily"},     {purpose: "weekly"},     {purpose: "monthly"} ]; 

(for simplicity i am omitting other attributes)

Now I want to have a method that returns a specific one of the objects if a matching purpose name is found.

This is not working:

function findPurpose(purposeName){     return $.grep(purposeObjects, function(){       return this.purpose == purposeName;     }); };  findPurpose("daily"); 

but it actually returns an empty array:

[] 

I am using JQuery 1.5.2. I have also tried with $.each() but with no luck. Apparently, most JQuery methods are designed for usage with DOM elements (such as filter().

Any ideas on how to achieve this?

Answer 1

No need for jQuery.

JavaScript arrays have a find method, so you can achieve that in one line:

array.find((o) => { return o[propertyName] === propertyValue }) 

Example

 const purposeObjects = [     {purpose: "daily"},     {purpose: "weekly"},     {purpose: "monthly"} ];  purposeObjects.find((o) => { return o["purpose"] === "weekly" })        // output -> {purpose: "weekly"} 

If you need IE compatibility, import this polyfill in your code.

Answer 2

you should pass reference on item in grep function:

function findPurpose(purposeName){     return $.grep(purposeObjects, function(item){       return item.purpose == purposeName;     }); }; 

Example