Conrad C-Control Pro Mega Series, Руководство пользователя

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120 Compiler
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5.3.6.6
Select Case
If depending on the value of an expression various commands should be executed then a Select
Case instruction seems to be an elegant solution:
Select Case Expression
Case constant_comparison 1
Instructions_ 1
Case constant_comparison 2
Instructions_ 2
.
.
Case constant_comparison_x
Instructions_x
Else ' Else is optional
Instructions
End Case
For constant comparisons special comparisons and ranges can be defined . Here examples for all
possibilities:
Comparison Execute on
Constant, = Constant Expression equal Constant
< Constant Expression smaller Constant
<= Constant Expression smaller equal Constant
> Constant Expression greater Constant
>= Constant Expression greater equal Constant
<> Constant Expression unequal Constant
Constant1 To Constant2 Constant1 <= Expression <= Constant2
The new features to use comparisons are introduced for Select Case statements with version
1.71. This extension is not available for CompactC switch statements.
The value of the Expression is calculated. Then the program execution will jump to the first constant
comparison that can be evaluated as true and will continue the program from there. If no constant
comparison can be fulfilled the Select Case construct will be left.
If an Else is defined within a Select Case instruction then the instructions after Else will be
executed if no constant comparison could be fulfilled.
Example:
Select Case a+ 2
Case 1
b=b* 2
Case = 5 * 5
b=b+ 2