VBScript conditional block

VBScript conditional blocks execute groups of code based on a "condition" being true. The two conditional statements, If and Select are explained here.

If statement

An If conditional statement allows you to have the code executed "if" something has the result of True.

If Var1 = 1 Then Call SomeFunction()

The above line will execute the line Call SomeFunction() if the Var1 = 1 is True.

If block

What if you want multiple lines to execute? To do that, the other way is the following (more common):

If Var1 = 1 Then
    AddQ "Var1 equals 1."
    Disconnect
End If

In this example, the AddQ function and the Disconnect function will be called when the if block executes.

Note that if the condition is false, the lines inside will be skipped over, but they must be valid VBScript (use comments if you want to hide something from the parser).

Else statement

Add an Else statement and something will always happen if the expression happens to be false:

If Var1 = 1 Then
    AddQ "Var1 equals 1."
Else
    AddQ "Var1 does not equal 1."
End If

If blocks can also be embedded:

If Var1 = 1 Then
    AddQ "Var1 equals 1."
Else
    If Var1 = 2 Then
        AddQ "Var1 equals 2."
    Else
        AddQ "Var1 does not equal 1 or 2."
    End If
End If

ElseIf statement

Using the ElseIf keyword, the above can be combined:

If Var1 = 1 Then
    AddQ "Var1 equals 1."
ElseIf Var1 = 2 Then
    AddQ "Var1 equals 2."
Else
    AddQ "Var1 does not equal 1 or 2."
End If

Notes

• Then is always required with an If or an ElseIf.
• There must be one If, zero or one Elses and zero to as many as needed ElseIfs.
• There is an If...Then...Else statement that can go on one line, but it is not very readable thus it is avoided.
• You cannot use the Exit statement with an If block like you can most other blocks.
• You should indent your code for readability based on the starting and ending of If blocks.

Select block

A Select block allows you to choose the course of action based on a value. It is basically a different structure to an If...ElseIf...Else block specifically made for when the same value is being compared repeatedly.

Syntax:

Select Case (VARIABLE)
    Case (VALUE)
        ' when (VARIABLE) = (VALUE)
        (STATEMENTS)
    Case (VALUE2)
        ' when (VARIABLE) = (VALUE2)
        (STATEMENTS)
    Case Else
        ' when (VARIABLE) is not any of the above
        (STATEMENTS)
End Select

The above If...ElseIf...Else block can be changed to:

Select Case Var1
    Case 1
        AddQ "Var1 equals 1."
    Case 2
        AddQ "Var1 equals 2."
    Case Else
        AddQ "Var1 does not equal 1 or 2."
End Select

Notes

• Case Else is optional depending on what you need, but it has to be the last case.
• You can do funky stuff like Select Case True and put variables as the Cases and whichever variable is equal to True first will determine which block is executed.
• You cannot use the Exit statement with a Select block like you can most other blocks.
• You can embed Select blocks inside other blocks.
• You should indent your code for readability based on the starting, ending, and Case statements of Select blocks.

See also

• VBScript function
• VBScript loop block
• VBScript class
• VBScript block
• VBScript language
• Script system