Revision [16566]

This is an old revision of KeyPgIif made by FxMwikki on 2013-02-01 09:08:29.

IIF

Conditional function that returns one of two values.

Syntax:
IIf ( condition, expr_if_true, expr_if_false )

Parameters:
condition
The condition to test.
A non-zero value evaluates as true, while a value of zero evaluates as false.
expr_if_true
An expression to evaluate and return if condition is true.
It must return:
• a numeric value, which can be an integer, floating point number or a pointer,
• or a string value,
• or an UDT value.
expr_if_false
An expression to evaluate and return if condition is false.
It must be same type as expr_if_true (either numeric, either string or UDT).

Description:
IIf returns a different numeric or string or UDT value depending of the result of a conditional expression. Its typical use is in the middle of an expression; it avoids splitting it to put a conditional in the middle.
IIf only evaluates the expression that it needs to return. This saves time, and can also be useful to prevent evaluating expressions that might be invalid depending on the condition.
Warning: The capacity to accept different numeric types to be mixed, strings and UDTs is only supported from the fbc version 0.25.

Examples:
Dim As Integer a, b, x, y, z
a = (x + y + IIf(b > 0, 4, 7)) \ z
is equivalent to:
Dim As Integer a, b, x, y, z, temp
If b > 0 Then temp = 4 Else temp = 7
a = (x + y + temp) \ z

Dim As Integer I
I = -10
Print I, IIf(I>0, "positive", IIf(I=0, "null", "negative"))
I = 0
Print I, IIf(I>0, "positive", IIf(I=0, "null", "negative"))
I = 10
Print I, IIf(I>0, "positive", IIf(I=0, "null", "negative"))
Sleep

Dialect Differences:

Differences from QB:
• New to FreeBASIC