Campbell CR9000, Инструкция по эксплуатации

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Section 9. Program Control Instructions
9-20
clause, only the statements following the first match are
executed.
Case Sets apart a group of CRBasic statements to be executed if
an expression in
expressionlist matches testexpression .
expressionlist The expressionlist consists of a comma-delimited list of one
or more of the following forms.
expression
expression To expression
Is compare-operator expression
statementblock
Elements statementblock-1 to statementblock-n consist of
any number of CRBasic statements on one or more lines.
Case Else Keyword indicating the statementblock to be executed if no
match is found between the testexpression and an
expressionlist in any of the other Case selections. When
there is no Case Else statement and no expression listed in
the Case clauses matches testexpression , program execution
continues at the statement following End Select .
End Select Ends the Select Case . Must appear after all other statements
in the Select Case control structure.
The argument expression list has these parts:
Part Description
expression Any numeric expression.
To Keyword used to specify a range of values. If you use the To
keyword to indicate a range of values, the smaller value must
precede To.
Although not required, it is a good idea to have a Case Else statement in your
Select Case block to handle unforeseen testexpression values.
You can use multiple expressions or ranges in each Case clause. For example,
the following line is valid:
Case 1 To 4, 7 To 9, 11, 13
Select Case statements can be nested. Each Select Case statement must have a
matching End Select statement.
Select Case Statement Example
The example uses Select Case to decide what action to take based on user
input.