ELSEIF - QB64Official/qb64 GitHub Wiki
ELSEIF is used in an IF...THEN block statement to offer an alternative condition.
Syntax
{code}
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{code}
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{alternative-code}
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Description
- ELSEIF statements require a separate code block line with THEN for each alternative condition.
 - There can be more than one ELSE IF statement in a single-line IF statement.
 - If there is only one possible alternative condition (such as 0 or NOT 0), use ELSE instead.
 - If the comparisons are based on multiple conditions being true, it may require many ELSEIF comparisons. ELSE could help cover some of those conditions.
 - You can use SELECT CASE when IF blocks have a long list of alterative ELSEIF conditions.
 
Relational Operators:
| Symbol | Condition | Example Usage | 
|---|---|---|
| = | Equal | IF a = b THEN | 
| <> | NOT equal | IF a <> b THEN | 
| < | Less than | IF a < b THEN | 
| > | Greater than | IF a > b THEN | 
| <= | Less than or equal | IF a <= b THEN | 
| >= | Greater than or equal | IF a >= b THEN | 
Example(s)
IF statement using ELSE IF in one statement line.
IF x = 100 THEN COLOR 10: PRINT x ELSE IF x > 100 THEN COLOR 12: PRINT x ELSE PRINT "< 100"
IF statement block
IF x = 100 THEN ' must place ANY code on next line!
  COLOR 10: PRINT x
ELSEIF x > 100 THEN COLOR 12: PRINT x
ELSE : PRINT "< 100"
END IF