Difference between revisions of "If and Then"
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− | This [[Keyword|keyword]] | + | This [[Keyword|keyword]] precedes a condition, is required to be followed by [[Then|then]] and may optionally be followed by [[Else|else]]. |
== If then == | == If then == | ||
Line 5: | Line 5: | ||
<delphi> | <delphi> | ||
if condition | if condition | ||
− | then | + | then true_statement |
− | else | + | else false_statement; |
</delphi> | </delphi> | ||
− | Condition is | + | Condition is a [[Boolean]] expression that evaluates to [[True|true]] or [[False|false]]. |
− | + | true_statement is executed if condition evaluates to true. | |
− | + | false_statement is executed if condition evaluates to false. | |
+ | An error occurs if condition does not evaluate to a boolean value. | ||
+ | |||
=== More statements in "if then" statement === | === More statements in "if then" statement === | ||
− | If you need two or more statements | + | If you need two or more statements for true_statement or false_statement, place them within a [[Begin|begin]] ... [[End|end]] [[Block]]. |
<delphi> | <delphi> |
Revision as of 21:58, 26 October 2010
This keyword precedes a condition, is required to be followed by then and may optionally be followed by else.
If then
<delphi>
if condition then true_statement else false_statement;
</delphi>
Condition is a Boolean expression that evaluates to true or false. true_statement is executed if condition evaluates to true. false_statement is executed if condition evaluates to false. An error occurs if condition does not evaluate to a boolean value.
More statements in "if then" statement
If you need two or more statements for true_statement or false_statement, place them within a begin ... end Block.
<delphi>
if boolean_condition then begin statement_one; statement_two; statement_three; end;
</delphi>
Keywords: begin — do — else — end — for — if — repeat — then — until — while