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    <p>I like to think of a delegate as "a pointer to a function". This goes back to C days, but the idea still holds. </p> <p>The idea is that you need to be able to invoke a piece of code, but that piece of code you're going to invoke isn't known until runtime. So you use a "delegate" for that purpose. Delegates come in handy for things like event handlers, and such, where you do different things based on different events, for example.</p> <p><a href="https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/delegates/using-delegates" rel="nofollow noreferrer">Here's</a> a reference for C# you can look at:</p> <p>In C#, for example, let's say we had a calculation we wanted to do and we wanted to use a different calculation method which we don't know until runtime. So we might have a couple calculation methods like this:</p> <pre><code>public static double CalcTotalMethod1(double amt) { return amt * .014; } public static double CalcTotalMethod2(double amt) { return amt * .056 + 42.43; } </code></pre> <p>We could declare a delegate signature like this:</p> <pre><code>public delegate double calcTotalDelegate(double amt); </code></pre> <p>And then we could declare a method which takes the delegate as a parameter like this:</p> <pre><code>public static double CalcMyTotal(double amt, calcTotalDelegate calcTotal) { return calcTotal(amt); } </code></pre> <p>And we could call the <code>CalcMyTotal</code> method passing in the delegate method we wanted to use.</p> <pre><code>double tot1 = CalcMyTotal(100.34, CalcTotalMethod1); double tot2 = CalcMyTotal(100.34, CalcTotalMethod2); Console.WriteLine(tot1); Console.WriteLine(tot2); </code></pre>
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    1. POWhat is Delegate?
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    1. CO+1 for the nod to the simple but effective function pointer in C.
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    2. COOne question related to your answer. How is it really different from calling a function in normal way? Just because of that it is not known at runtime ?
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    3. CO@NAVEED - refer to my latest edit, I included an example. As far as the actual method call, it doesn't look any different from a normal method call in my example above (the calcTotal(amt) is calling the delegate), but the power of delegates is that you can use them as parameters, etc. when you want a method to be able to have different behavior. There are many other things you can use them for also, this is just a simple example. Hope that helps.
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