79 lines
2.8 KiB
HTML
79 lines
2.8 KiB
HTML
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<HTML>
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<HEAD><TITLE>QuickBASIC 3.0 - Long Entry</TITLE></HEAD>
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<BODY>
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<A HREF="ng2c723.html">[<<Previous Entry]</A>
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<A HREF="ng320.html">[^^Up^^]</A>
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<A HREF="ng2db1d.html">[Next Entry>>]</A>
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<A HREF="menu.html" >[Menu]</A>
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<A HREF="info.html">[About The Guide]</A>
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<HR>
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<PRE>
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<B>SELECT Case Structure</B>
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<B>SELECT</B> <B>CASE</B> <U>expression</U>
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<B>CASE</B> <U>testlist</U>
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.
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. <U>statements</U>
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.
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[CASE <U>testlist</U>
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.
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. <U>statements</U>
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.]
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[CASE ELSE
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.
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. <U>statements</U>
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.]
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<B>END</B> <B>SELECT</B>
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Compares an expression against one or more values and directs
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execution flow in accordance with the result.
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<U>expression</U> An expression of any type.
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<U>testlist</U> A comma-delimited list of expressions (see further
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description, below) that test the value of expression.
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-----------------------------------------------------------------------
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<B>Notes:</B> The elements of a given <U>testlist</U> argument are implicitly
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ORed. Therefore, the statements following CASE <U>testlist</U>
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are executed if any member of <U>testlist</U> is true. Following
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execution of those statements, control passes to the first
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statement following END SELECT.
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The SELECT CASE structure may include any number of CASE
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<U>testlist</U> clauses but must include at least one. All CASE
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<U>testlist</U> clauses must appear before the optional CASE ELSE
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clause.
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The statements following CASE ELSE are executed if all
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elements in all CASE <U>testlist</U> clauses are false.
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The <U>testlist</U> argument may include the following kinds of
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tests: equality, inequality, greater than, less than, and
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range. Examples of each are as follows:
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CASE 100
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CASE IS = 100
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CASE IS <> "Yomama"
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CASE IS > -5
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CASE IS < 2E15
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CASE 5 TO 10
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Note that the = operator is optional for the equality
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test, and that the keyword IS must be used before any
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relational operator. In the range test, the smaller of the
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two values must appear before the keyword TO.
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The SELECT CASE structure is equivalent to a set of nested
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IF/THEN/ELSE statements but produces more readable source
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code.
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</PRE>
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<HR>
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This page created by ng2html v1.05, the Norton guide to HTML conversion utility.
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Written by <A HREF="http://www.acemake.com/hagbard">Dave Pearson</A>
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<HR>
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</BODY>
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</HTML>
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