Find if an element exists in Javascript array

Question

I am trying to find if an element exists in Array with a name. Couldn't figure out, how to achieve the same

let string = [{"plugin":[""]}, {"test": "123"}]
console.log(string);
console.log(string instanceof Array); //true
console.log("plugin" in string); //false

Answer 1

plugin is not defined directly in the array, it is defined inside the object in the array.

Use the Array#find to check if any element in the array contain the given property.

array.find(o => o.hasOwnProperty('plugin'))

Use hasOwnProperty to check if object is having property.

 let array = [{"plugin":[""]}, {"test": "123"}]; let res = array.find(o => o.hasOwnProperty('plugin')); console.log(res); 

As an option, you can also use Array#filter .

array.filter(o => o.hasOwnProperty('plugin')).length > 0;

 let array = [{"plugin":[""]}, {"test": "123"}]; let containsPlugin = array.filter(o => o.hasOwnProperty('plugin')).length > 0; console.log(containsPlugin); 

Answer 2

You can use Array#some() and Object.keys() and return true/false if object with specific key exists in array.

 let string = [{"plugin":[""]}, {"test": "123"}]; var result = string.some(o => Object.keys(o).indexOf('plugin') != -1); console.log(result) 

Answer 3

take a look at following example code as a general answer for finding an element in an array in Javasript:

var power = [
    "Superman",
    "Wonder Woman",
    "Batman"
];

for (var i = 0; i < power.length && power[i] !== "Wonder Woman"; i++) {
    // No internal logic is necessary.
}

var rank = i + 1;

// Outputs: "Wonder Woman's rank is 2"
console.log("Wonder Woman's rank is " + rank);

I hope it can help you.

Answer 4

use like this

let array = [{"plugin":[""]}, {"test": "123"}];
array.find(o => o.plugin).length