Understanding Custom Generic Methods in C#

In this blogI will show how Method overloading can be achieved with Custom Generic Methods –and in this process will explain Custom Generic method.

Let's understand it with Swapping of 2 numbers program.

Say You need to swap 2 integers - you would write-

static void Swap(ref int a, ref int b)
{
    int temp;
    temp = a;
    a = b;
    b = temp;
}

Now assume you need to write code for swapping of 2 strings

static void Swap(ref string a, ref string b)
{
    string temp;
    temp = a;
    a = b;
    b = temp;
}

Now if you need to Swap 2 floats, or a user 2 defined Class type then you would need to go and write corresponding version of Swap methods – Right??- Then it would be bit tedious.

Yeah – I know – few of you would have thought by now- that you can replace all these version of Swap methods by a single[Non Generic] method which will be operating on object parameters.

But then you face all the problems of Boxing, Unboxing, Type Safety issue, explicit casting and so on…

So came the Generics -> So in other words if we have a bunch of overloaded methods which vary by incoming arguments – Generic method is the better answer for it.

So lets see how we can code a generic method for Swap() which would work for all types

//This method would swap any 2 items as specified by parameter Type T

static void Swap<T>(ref T a, ref T b)

{
    T temp;
    temp = a;
   a = b;
    b = temp;
}

So here our Generic Swap method can operate on any 2 parameters of Type<T>

With this approach of Custom Generic method – We have only one version of Swap<T>() to maintain and it can operate in a type safe manner on any 2 items of a given type.

Since there is no casting required from (Value type ? ? Reference Type) ? So stack based items stay on the Stack ,while Heap based items stay on the Heap.

I have attached the Source Code used for this explanation.

Happy Learning!