Stephens' C# Programming with Visual Studio® 2010 24-Hour Trainer

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LESSON 28 Making generic classes

Lesson Requirements

Start a new project and give it an

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ArrayMethods class.

Create a generic

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Randomize method with one generic type parameter T. The method should

take as a parameter an array of

T and return an array of T.

Make the main program test the method.

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Hints

Use the following code for the method’s body. Try to figure out the method’s declaration

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yourself before you read the step-by-step instructions that follow.

// Make a Random object to use to pick random items.

Random rand = new Random();

// Make a copy of the array so we don’t mess up the original.

T[] randomizedItems = (T[])items.Clone();

// For each spot in the array, pick

// a random item to swap into that spot.

for (int i = 0; i < items.Length - 1; i++)

{

// Pick a random item j between i and the last item.

int j = rand.Next(i, items.Length);

// Swap item j into position i.

T temp = randomizedItems[i];

randomizedItems[i] = randomizedItems[j];

randomizedItems[j] = temp;

}

// Return the randomized array.

return randomizedItems;

Step-by-Step

Start a new project and give it an



ArrayMethods class.

1. This is reasonably straightforward. You don’t need to make the ArrayMethods class

generic.

Create a generic



Randomize method with one generic type parameter T. The method should

take as a parameter an array of

T and return an array of T.

1. The following code shows how you can implement ...