20021201
Syntax 4:
If
䡺
<expression>
Then
[<statement>] …
ElseIf
䡺
<expression>
Then
[<statement>] …
Else
[<statement>] …
IfEnd
Function 4
• If the expression is true, the statement in the
If Then
block is executed. After that,
execution advances to the next statement after
IfEnd
.
• If the
If
command expression is false, the
ElseIf
command expression is tested. If it is true,
the statement in the
ElseIf Then
block is executed. After that, execution advances to the
next statement after
IfEnd
. If it is false, the
Else
block statement is executed. After that,
execution advances to the next statement after
IfEnd
.
Description
• With all four of the syntaxes described above, you can use a multi-statement command (
:
)
in place of the carriage return to separate
Then
block statements.
• The
If~IfEnd
command can be nested.
Example: Input a
Input b
If a < 0
Then
0
S
a
If b < 0
Then
0
S
b
IfEnd
IfEnd
• The
If~IfEnd
loop can be exited using the
Break
command or
Return
command.
• It is always a bad idea to use the
Goto
command to exit an
If~IfEnd
loop. Not only is it
poor programming, it can cause problems due to improper termination of internal
processes used by
If
.
12-6-12
Program Command Reference
}
If Then <block>
}
ElseIf Then <block>
}
Else <block>
