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operator at the time you declare your array. However, you will get an error if you try to assign values this way after the array has been created. The following are some examples showing different ways to initialize an array. Note that you can either assign a list of values or you can set the number of values allowed and then assign them later. The first example uses an initializer list, just as before: VB .NET 'The short version Dim numbers As Integer() = {1, 2, 3, 4, 5} Dim names As String() = {"Bob", "Sue", "Tim"} 'The long version Dim numbers As Integer() = New Integer(4) {1, 2, 3, 4, 5} Dim names As String() = New String(2) {"Bob", "Sue", "Tim"} C# //The short version int[] numbers = { 1, 2, 3, 4, 5 }; string[] names = { "Bob", "Sue", "Tim" }; //The long version int[] numbers = new int[5] {1, 2, 3, 4, 5}; string[] names = new string[3] {"Bob", "Sue", "Tim"}; In both of these examples, we used an initializer list to add elements at the same time we created the variables; but in the long version of the VB .NET code, the number inside the parentheses is a 4, while in the C# version, it is a 5. This is because the 4 in the VB .NET version indicates the highest index number allowed: 0 to 4. The 5 in the C# version indicates the amount of values it will accept. Another common way to add data to an array is by telling the computer how many elements there will be and then setting the values later. For example, let s say that you want to create an array of integers; you would tell the computer what type to use and how many integers to expect later. Note that this syntax replaces using the initializer list, so you would not see both being used on the one line: VB .NET Dim MyDemoArray() As String = {"One", "Two"} 'Ok Dim MyDemoArray2(1) As String 'Still Ok, but has not set any values yet. Dim MyDemoArray3(1) as String = {"One", "Two"} 'NOT Ok, will cause an error C# string[]MyDemoArray = {"One", "Two"}; // Ok string[2]MyDemoArray; //Still Ok, but has not set any values yet. string[2]MyDemoArray = {"One", "Two"}; //NOT Ok, will cause an error Again, notice that the index value in this example is different in the VB .NET and C# versions of the code. Remember that in VB .NET, you need to tell the computer the highest index number to allow; if the program goes beyond that index number, then an error will be

thrown. Since C# is different, you stipulate the number of elements you want to hold, not the highest index number. In the next code example, we show how to set the individual values after the array has been created. Notice that we use the same index number for each language. VB .NET Dim numbers(2) As Integer 'numbers is a 3-element array (0,1,2) numbers(0) = 5 numbers(1) = 10 numbers(2) = 15 numbers(3) = 20 'cause an error because it is outside the index range C# int[] numbers = new int[2]; // numbers is a 2-element array (0,1) numbers[0] = 5; numbers[1] = 10; numbers[2] = 15; //cause an error because it is outside the index range numbers[3] = 20; //cause an error because it is outside the index range The VB .NET version of this code worked until it got to the index of 3, while the C# had an error after 1. Since the C# index number is set at [2], many people expect the index of 2 will work. This type of bug is so common that it has its own name it s known as an off by one error.