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63 lines
1.6 KiB
Markdown
63 lines
1.6 KiB
Markdown
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[ELSEIF](ELSEIF) is used in an [IF...THEN](IF...THEN) block statement to offer an alternative condition.
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## Syntax
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> [IF](IF) condition [THEN](THEN)
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> *{code}*
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> ⋮
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> [ELSEIF](ELSEIF) condition2 [THEN](THEN)
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> *{code}*
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> ⋮
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> [ELSE](ELSE)
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> *{alternative-code}*
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> ⋮
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> [END IF](END-IF)
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## Description
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* ELSEIF statements require a **separate** code block line with [THEN](THEN) for each alternative condition.
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* There can be more than one [ELSE](ELSE) IF statement in a single-line IF statement.
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* If there is only one possible alternative condition (such as 0 or [NOT](NOT) 0), use [ELSE](ELSE) instead.
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* If the comparisons are based on multiple conditions being true, it may require many ELSEIF comparisons. ELSE could help cover some of those conditions.
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* You can use [SELECT CASE](SELECT-CASE) when IF blocks have a long list of alterative ELSEIF conditions.
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**Relational Operators:**
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| Symbol | Condition | Example Usage |
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| -- | -- | -- |
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| = | Equal | IF a = b THEN |
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| <> | NOT equal | IF a <> b THEN |
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| < | Less than | IF a < b THEN |
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| > | Greater than | IF a > b THEN |
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| <= | Less than or equal | IF a <= b THEN |
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| >= | Greater than or equal | IF a >= b THEN |
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## Example(s)
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IF statement using ELSE IF in one statement line.
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```vb
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IF x = 100 THEN COLOR 10: PRINT x ELSE IF x > 100 THEN COLOR 12: PRINT x ELSE PRINT "< 100"
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```
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IF statement block
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```vb
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IF x = 100 THEN ' must place ANY code on next line!
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COLOR 10: PRINT x
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ELSEIF x > 100 THEN COLOR 12: PRINT x
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ELSE : PRINT "< 100"
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END IF
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```
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## See Also
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*[ELSE](ELSE), [END IF](END-IF)
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*[IF...THEN](IF...THEN)
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