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			A100222: When to Use Parentheses with a Subroutine or Function in VB/VBA/VBScript. When to use, or not to use, parentheses ( ) with a VB, VBA, or VBScript subroutine or function can be a bit confusing. We will first examine how to set up the code structure for a subroutine and function, and then we will look at how to call that subroutine or function. Subroutine Code Structure If a subroutine does not receive any arguments, then you do not use any parentheses when declaring the subroutine. Note the required use of the Sub and End Sub statements which define the start and finish of the subroutine code. Sub MySubroutine 'place your code here End Sub However, if a subroutine does receive arguments, then you must use parentheses in its declaration. If there is more than one argument, you must separate the arguments with commas. Sub MySubroutine(intUsageFee, intTimeInHours, strCompanyName) 'place your code here End Sub Function Code Structure As with subroutines, if a function does not receive any arguments, then you do not use any parentheses in the function declaration. Note the required use of the Function and End Function statements which define the start and finish of the function code. Function MyFunction 'place your code here End Function However, if a function does receive arguments, then you must enclose its argument list in parentheses when declaring the function. If there is more than one argument, you must separate the arguments with commas. Function MyFunction(intUsageFee, intTimeInHours, strCompanyName) 'place your code here End Function Calling the Subroutine There are two possible ways to call a subroutine. You may either call the subroutine directly by name only, or you may call it by using the VBScript Call statement. Calling a Subroutine by Name If a subroutine does not pass any arguments, then you do not use any parentheses. MySubroutine Even if a subroutine has arguments, you still do not use parentheses. If there is more than one argument, you must separate the arguments with commas. If you enclose the argument list in parentheses when attempting to call a subroutine that takes more than one argument, you will receive the runtime error "Cannot use parentheses when calling a Sub". MySubroutine intUsageFee, intTimeInHours, "DevGuru" Using the VBScript Call Statement to Call a Subroutine The use of Call statement is optional when you wish to call a subroutine. The purpose of the Call statement when used with a Sub is to allow you to enclose the argument list in parentheses. However, if a subroutine does not pass any arguments, then you still should not use parentheses when calling a Sub using the Call statement. Call MySubroutine If a subroutine has arguments, you must use parentheses when using the Call statement. If there is more than one argument, you must separate the arguments with commas. Call MySubroutine(intUsageFee, intTimeInHours, "DevGuru") Calling the Function There are two possible ways to call a function. You may either call the function directly, by name only, or you may call it by using the VBScript Call statement. Calling a Function by Name When calling a function directly by name and when there is no assignment to a returned value, all of the following are legal syntax: MyFunction MyFunction() MyFunction intUsageFee, intTimeInHours, "DevGuru" If you want a returned value, you can assign the function to a variable. Note that if there is one or more arguments, you must use the parentheses. returnval = MyFunction returnval = MyFunction() returnval = MyFunction(intUsageFee, intTimeInHours, "DevGuru") Using the Call Statement If a function has arguments, you must use parentheses when using the Call statement. If there is more than one argument, you must separate the arguments with commas. There is no returned value when using Call. Call MyFunction(intUsageFee, intTimeInHours, "DevGuru") The Guru