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copied!<p>If you want <code>this</code> captured the TypeScript way of doing this is via arrow functions. To quote Anders:</p> <blockquote> <p>The <code>this</code> in arrow functions is lexically scoped</p> </blockquote> <p>Here is the way I like to use this to my advantage:</p> <pre><code>class test{ // Use arrow functions func1=(arg:string)=>{ return arg+" yeah" + this.prop; } func2=(arg:number)=>{ return arg+10 + this.prop; } // some property on this prop = 10; } </code></pre> <p><a href="http://www.typescriptlang.org/Playground/#src=class%20test%7B%0A%09%2F%2F%20Use%20arrow%20functions%0A%09func1%3D(arg%3Astring)%3D%3E%7B%0A%09%09%09return%20arg%2B%22%20yeah%22%20%2B%20this.prop%3B%0A%09%7D%0A%09func2%3D(arg%3Anumber)%3D%3E%7B%0A%09%09%09return%20arg%2B10%20%2B%20this.prop%3B%0A%09%7D%09%09%0A%09%09%0A%09%2F%2F%20some%20property%20on%20this%0A%09prop%20%3D%2010%3B%0A%7D" rel="noreferrer">View this in the TypeScript Playground</a></p> <p>You can see that in the generated JavaScript <code>this</code> is captured <em>outside</em> the function call:</p> <pre><code>var _this = this; this.prop = 10; this.func1 = function (arg) { return arg + " yeah" + _this.prop; }; </code></pre> <p>so the <code>this</code> value inside the function call (which could be <code>window</code>) would not be used.</p> <p>To learn more: <a href="https://www.youtube.com/watch?v=tvocUcbCupA&hd=1" rel="noreferrer">“Understanding <code>this</code> in TypeScript” (4:05) – YouTube</a></p>

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