Prepare!

One of the most elegant built-in operations in C, C++, Java, and JavaScript is the Ternary conditional operator, typically expressed as:

variable = (boolTest) ? trueExpression : falseExpression;

...which is equivalent to this 'if-then-else' pseudo-code:

if (boolTest) {
   variable = trueExpression
} else {
   variable = falseExpression;
}

Using VBScript, I've always missed the simplicity offered by Ternary conditional operators. That is, until I started using the built-in Array() function, and determining the appropriate array index based on a logical test. For example:

Dim result : result = Array("Failure", "Success")(Abs(0 = Err.Number))

In this VBScript example, the "Failure" string is the falseExpression, and the "Success" string is the trueExpression. The "(Abs(0 = Err.Number))" is the actual boolTest. Here, the built-in Abs() function must be used, because VBScript "True" is actually -1, which would return an invalid array index. Recall: We need the array indexes to be either 0 or 1 (not -1).

Although, if you need to invoke a function for the result, then use the built-in Eval() function, like so:

Function Failure()
   ' Some lines of code here
   Failure = "Error (" & Err.Number & "): " & Err.Description
End Function

Function Success()
   ' Some lines of code here
   Success = "Whatever you want it to be"
End Function

Dim result : result = Eval(Array("Failure", "Success")(Abs(0 = Err.Number)))

In this example, "Success" will be returned to the built-in Eval() function if the Err.Number is 0, which invokes the Function Success() and returns its result. Otherwise, if Err.Number is not 0, then "Failure" will be returned to the built-in Eval() function, which invokes the Function Failure() and returns the result to the variable by the same name.

At the very least, I hope these simple examples help reduce some of your VBScript code, which may be plagued by multiple lines of If-Then-Else-End If conditional blocks.

Enjoy.