How to check if a string “StartsWith” another string?

You can use ECMAScript 6’s String.prototype.startsWith() method, but it’s not yet supported in all browsers. You’ll want to use a shim/polyfill to add it on browsers that don’t support it. Creating an implementation that complies with all the details laid out in the spec is a little complicated. If you want a faithful shim, use either:

Once you’ve shimmed the method (or if you’re only supporting browsers and JavaScript engines that already have it), you can use it like this:

   console.log("Hello World!".startsWith("He")); // true
var haystack = "Hello world";
var prefix = 'orl';
console.log(haystack.startsWith(prefix)); // false

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