You can use For...Next statements to run a block of statements a specific number of times. For loops, use a counter variable whose value increases or decreases with each repetition of the loop.
The following example causes a procedure called MyProc
to execute 50 times. The For statement specifies the counter variable x and its start and end values. The Next statement increments the counter variable by 1.
Sub DoMyProc50Times()
Dim x
For x = 1 To 50
MyProc
Next
End Sub
Using the Step keyword, you can increase or decrease the counter variable by the value you specify. In the following example, the counter variable j is incremented by 2 each time the loop repeats. When the loop is finished, the total is the sum of 2, 4, 6, 8, and 10.
Sub TwosTotal()
Dim j, total
For j = 2 To 10 Step 2
total = total + j
Next
MsgBox "The total is " & total
End Sub
To decrease the counter variable, use a negative Step value. You must specify an end value that is less than the start value. In the following example, the counter variable myNum
is decreased by 2 each time the loop repeats. When the loop is finished, total is the sum of 16, 14, 12, 10, 8, 6, 4, and 2.
Sub NewTotal()
Dim myNum, total
For myNum = 16 To 2 Step -2
total = total + myNum
Next
MsgBox "The total is " & total
End Sub
You can exit any For...Next statement before the counter reaches its end value by using the Exit For statement. Because you usually want to exit only in certain situations, such as when an error occurs, you should use the Exit For statement in the True statement block of an If...Then...Else statement. If the condition is False, the loop runs as usual.
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