On…GoTo, On…GoSub

Branch to one of several specified lines, depending on the value of an expression.

Syntax:

On expression GoTo destinationlist
On expression GoSub destinationlist

expression: Any numeric expression that evaluates to a whole number between 0 and 255, inclusive. If expression is any number other than a whole number, it is rounded before it is evaluated.
destinationlist: List of line numbers or line labels separated by commas.

The value of expression determines which line is branched to in destinationlist. If the value of expression is less than 1 or greater than the number of items in the list, one of the following results occurs:

If expression is	Then
Equal to 0	Control drops to the statement following On…GoSub or On…GoTo.
Greater than the number of items in the list	Control drops to the statement following On…GoSub or On…GoTo.
Negative	An error occurs.
Greater than 255	An error occurs.

Line numbers and line labels can be mixed in the same list. Any number of line labels and line numbers can be used with On…GoSub and On…GoTo. However, when more labels or numbers are present than fit on a single line, the line-continuation character must be used to continue the logical line onto the next physical line.

Tip

Select Case provides a more structured and flexible way to perform multiple branching.

Example

This example uses the On…GoSub and On…GoTo statements to branch to subroutines and line labels, respectively.

Sub OnGosubGotoDemo()
    Dim Number, MyString
    Number = 2 ' Initialize variable.
    ' Branch to Sub2.
    On Number GoSub Sub1, Sub2 ' Execution resumes here after On...GoSub.
    On Number GoTo Line1, Line2 ' Branch to Line2.
    ' Execution does not resume here after On...GoTo.
    Exit Sub
Sub1:
    MyString = "In Sub1" : Return
Sub2:
    MyString = "In Sub2" : Return
Line1:
    MyString = "In Line1"
Line2:
    MyString = "In Line2"
End Sub

On…GoTo, On…GoSub

Example

See Also