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Pass Values Through Reference

Where possible, it is recommended that you pass a value through a reference and not through a variable. Passing a value through a variable is less efficient then passing the same value through a reference. You must not pass a value through a variable unless you cannot pass the same value through a reference.

Passing a Value Through a Reference

Siebel CRM can pass a variable to a subroutine or a function through a reference. Each method determines if it can receive a value from a variable or a reference. A subroutine or function can change this value.

Passing a Value Through a Variable

Siebel CRM can pass a value to a function through a variable. After processing is complete, the variable retains the value that it contained before Siebel CRM passes it, even though the subroutine or function might change the passed value.

If you configure Siebel CRM to pass a variable to a method that modifies the corresponding argument, and if you must retain the value that this variable contains, then you must enclose the variable in parentheses in the Call Subroutine statement. This format instructs Siebel VB to pass a copy of the variable. This technique is known as passing a value through a variable. For more information, see Call Subroutine Method.

If Siebel CRM passes a variable to a function, and if an argument for that function expects to receive a value through reference, then that variable must match the exact type of the argument. This requirement does not apply to an expression or a variant.

If you configure Siebel CRM to call an external DLL, then you can use the ByVal keyword to configure it to pass an argument by value. You specify this configuration in the Declare Procedure statement or in the Call Subroutine statement. If you specify the ByVal keyword in the declaration, then the ByVal keyword is optional in the call. If you use the ByVal keyword, then it must precede the value. If you do not specify the ByVal keyword in the declaration, and if you specify the data type in the declaration, then you cannot use the ByVal keyword in the call.

For more information, see Declare Procedure Method.