.includes() not working in Internet Explorer

This code does not work in internet explorer. Any alternative?

"abcde".includes("cd")

String.prototype.includes is, as you write, not supported in Internet Explorer (or Opera).

Instead you can use String.prototype.indexOf. #indexOf returns the index of the first character of the substring if it is in the string, otherwise it returns -1. (Much like the Array equivalent)

var myString = 'this is my string';
myString.indexOf('string');
// -> 11

myString.indexOf('hello');
// -> -1

MDN has a polyfill for includes using indexOf: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/String/includes#Polyfill

EDIT: Opera supports includes as of version 28.

EDIT 2: Current versions of Edge supports the method. (as of 2019)

Or just put this in a Javascript file and have a good day :)

String.prototype.includes = function (str) {
  var returnValue = false;

  if (this.indexOf(str) !== -1) {
    returnValue = true;
  }

  return returnValue;
}

includes() is not supported by most browsers. Your options are either to use

-polyfill from MDN https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/String/includes

or to use

-indexof()

var str = "abcde";
var n = str.indexOf("cd");

Which gives you n=2

This is widely supported.

Problem:

Try running below(without solution) from Internet Explorer and see the result.

console.log("abcde".includes("cd"));

Solution:

Now run below solution and check the result

if (!String.prototype.includes) {//To check browser supports or not
  String.prototype.includes = function (str) {//If not supported, then define the method
    return this.indexOf(str) !== -1;
  }
}
console.log("abcde".includes("cd"));

This one may be better and shorter:

function stringIncludes(a, b) {
	return a.indexOf(b) >= 0;
}

I had the same problem when working in Angular 5. In order to make it work directly without writing a polyfill yourself, just add the following line to polyfills.ts file:

import "core-js/es7/array"

Also, tsconfig.json lib section might be relevant:

"lib": [
  "es2017",
  "dom"
],

For react:

import 'react-app-polyfill/ie11';
import 'core-js/es5';
import 'core-js/es6';
import 'core-js/es7';

Issue resolve for - includes(), find(), and so on..

If you want to keep using the Array.prototype.include() in javascript you can use this script: github-script-ie-include That converts automatically the include() to the match() function if it detects IE.

Other option is using always thestring.match(Regex(expression))

It works for me:

function stringIncludes(a, b) {
      return a.indexOf(b) !== -1;
}

this is because ie does not support includes so Make a dot function and use it just like es6 includes() in es5 as below :

String.prototype.includes = function (str) {
 return this.indexOf(str) !== -1;
}

Following is the string

var myString = 'this is my string';

Checking the match as following:

console.log(myString.includes('string')); // true
console.log(myString.includes('street')); //false

Now you can add this for ES5 using same indexOf in includes way

You can do the same with !! and ~ operators

 var myString = 'this is my string';
    
 !!~myString.indexOf('string');
 // -> true
    
 !!~myString.indexOf('hello');
 // -> false

here's the explanation of the two operators (!! and ~ )

https://stackoverflow.com/questions/784929/what-is-the-not-not-operator-in-javascript

https://www.joezimjs.com/javascript/great-mystery-of-the-tilde/