SELECT CASE
(Statement)
Execute the statement block associated with the matching condition out of multiple conditions.
SELECT CASE <expression>
CASE <item>[,<item>...]
:
[CASE ELSE]
END SELECT
This statement evaluates <expression> and compares it with <item> of the first CASE statement. If a match is found, the statement block following the first CASE statement is executed. If the <item> of the first CASE statement does not match, comparisons are made with <item> of the subsequent CASE statement.
<expression> is an arithmetic expression or a character string.
<item> is a variable, a constant, an expression or a conditional expression. The conditional expression can be specified as follows.
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<arithmetic expression 1> TO <arithmetic expression 2>This checks whether the result of <expression> is any value between <arithmetic expression 1> and <arithmetic expression 2>. The TO keyword cannot be used if <expression> is a character string.
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IS <comparison operator> <arithmetic expression>This compares the result of <expression> with the value of <arithmetic expression>. If <expression> is a character string, <comparison operator> can be "=" only.
The CASE ELSE statement executes if <expression> does not match any of CASE statements.
CASE ELSE should precede END SELECT.
REM Evaluate more than one condition
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SELECT CASE Index
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'If the index value and the CASE statement value match,
'the command executes
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CASE 0
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'If the index is 0
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STOP
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'Stop program execution
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CASE 1
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'If the index is 1
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HALT "STOP"
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'Stop program execution
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CASE 2
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'If the index is 2
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HOLD "STOP"
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'Stop program execution temporarily
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CASE 3
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'If the index is 3
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STOPEND
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'Cycle-stop a continuously executed program
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CASE 4
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'If the index is 4
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ON li1 + li2 GOSUB *samp1, *samp2, *samp3
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'Call a subroutine beginning with the nth labelname
'depending upon the value n of li1+li2
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CASE 5
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'If the index is 5
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ON li1 + li2 GOTO *samp1, *samp2, *samp3
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'Jump to the nth label depending upon the value n of li1+li2
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CASE 6 TO 8
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'If the index is 6 to 8
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PRINTDBG "Reservation"
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'Output a message to the debug window
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CASE IS ≥ 9
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'If the index is 9 or greater
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END
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'Declare the end of motion executed by the program
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END SELECT
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'Declare the end of conditions evaluation statement
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