How Can I Implement C#'s String.StartsWith() Functionality in JavaScript?

Implementing String.StartsWith() in JavaScript

JavaScript does not natively provide a direct equivalent of C#'s String.StartsWith method. However, with the introduction of ECMAScript 2015 (ES6), the String.prototype.startsWith() method was added as a standard feature.

Unfortunately, at the time of this writing, ES6 browser support is still limited. Therefore, if you need to use this functionality in older browsers, you will need to utilize a shim or polyfill.

Polyfill Implementation

To implement a shim that faithfully adheres to the ES6 specification, consider using either:

• Matthias Bynens's String.prototype.startsWith shim
• The es6-shim, which offers a comprehensive shim for various ES6 features, including String.prototype.startsWith

Example Usage

Once you have installed the shim, you can use the String.prototype.startsWith() method as follows:

console.log("Hello World!".startsWith("He")); // true

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

The above is the detailed content of How Can I Implement C#'s String.StartsWith() Functionality in JavaScript?. For more information, please follow other related articles on the PHP Chinese website!