Default parameters for implementing user-defined functions in ASP (VBScript)

All functions in modern languages can have default parameters. Functions built in VBScript systems can have optional values (such as common split () and so on ), however, this function is not available in our own defined functions.

The following provides a method to implement the optional parameter function. Functin Foo (dtype, dsize, value)
Dim a, B
If typename (dtype) <> "error" then
A = dtype
Else
A = "Default Value"
End if
If typename (dsize) <> "error" then
B = dsize
Else
B =-1
End if
.
End Function

As shown in the sample code, dtype and dsize In the foo function are optional functions. You can pass parameters or do not pass parameters when calling them. when no parameter is passed, the comma placeholder cannot be lost, that is, the Foo (, "myvalue") format should be used.