Index of element in Visual Basic .NET

In Visual Basic .NET, you can get the index of an element in an array using the Array.IndexOf method. This method returns the index of the first occurrence of the specified value in the array.

Here's an example of how to get the index of an element in a one-dimensional array:

Dim arr As Integer() = {1, 2, 3, 4, 5}
Dim index As Integer = Array.IndexOf(arr, 3)
Console.WriteLine("Index of 3: " & index) ' Output: 2

In this example, we create an integer array with five elements and initialize it with values. Then, we call the Array.IndexOf method to get the index of the value 3 in the array. The method returns the index 2, which we assign to the index variable.

Here's an example of how to get the index of an element in a two-dimensional array:

Dim arr(,) As Integer = {{1, 2}, {3, 4}, {5, 6}}
Dim index As Integer = -1
For i As Integer = 0 To arr.GetLength(0) - 1

    For j As Integer = 0 To arr.GetLength(1) - 1

        If arr(i, j) = 4 Then

            index = i

            Exit For

        End If

    Next

    If index <> -1 Then Exit For

Next
Console.WriteLine("Index of 4: " & index) ' Output: 1

In this example, we create a two-dimensional integer array with three rows and two columns and initialize it with values. Then, we loop through each element in the array and check if it equals 4. If we find a match, we assign the row index to the index variable and exit the loop. Finally, we print the index of the value 4 in the array.