JS: String.prototype.startsWith

By Xah Lee. Date: . Last updated: .

New in ES2015.

s.startsWith ( searchString )

s.startsWith ( searchString, position )

Return true if s starts with searchString from position. By default, position is 0. Else, returns false.

const ss = "abcd";

console.log ( ss.startsWith("ab") ); // true
console.log ( ss.startsWith("b") );  // false

console.log ( ss.startsWith("b", 1) ); // true

Reference

ECMAScript 2015 §Text Processing#sec-string.prototype.startswith

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