|
Currently, single-line if... then statements cannot contain an else clause. The elseif syntax is not currently supported at all (even on multi-line if... then statements). |
|
If.... Then... Else Statement |
Top Previous Next |
Function: |
A way to conditionally execute code. |
Syntax: |
if expression then statement1 statement2 … [ else statement1 statement2 … ] end if
or:
if expression then true_statement1 : true_statement2 … |
Scope: |
Local and HTML |
See Also: |
Part |
Description |
expression |
Required. The result of this expression (true or false) is then used to determine what code will execute. |
statement[1, 2...] |
Required. Statements to execute. |
: |
Optional. Separator for multiple statements on a single line. Covered under Programming Fundamentals. |
Details
When the expression evaluates to true, the block of code immediately following the then keyword is executed. If it evaluates to false, the code immediately following the else keyword is executed; if there is no else keyword, program flow resumes from the line immediately following the end if keyword.
When using the single-line syntax (as in the lower example above), an if statement must not be terminated using an end if. This is the only construct under Tibbo Basic where line end matters. So, if you want to have several statements in such a construct, you need to place them all in the same line, and separate them with colons.
If... then... else statements may be nested.
|
Currently, single-line if... then statements cannot contain an else clause. The elseif syntax is not currently supported at all (even on multi-line if... then statements). |
Examples
if net.failure=1 then if sys.runmode=0 then ser.setdata("Ethernet failure!"):ser.send 'massage when in debug mode sys.halt else if net.linkstate=0 then ser.setdata("No Ethernet link!") else if net.linkstate=1 then ser.setdata("Linked at 10Mbit/s.") else ser.setdata("Linked at 100Mbit/s.") end if end if ser.send end if
|
