IF-THEN-ELSE-END IF

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IF-THEN-ELSE-END IF
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= <span class="f_Header">Action</span> =
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Allows conditional execution or branching, based on the evaluation of a Boolean expression.
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<span style="font-family: Arial;">&nbsp;</span>
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<span style="font-family: Arial;">&nbsp;</span>
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= <span class="f_Header">Syntax</span> =
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<span class="f_Syntax">IF</span>&nbsp;expression<span class="f_Syntax">&nbsp;THEN</span>
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<span style="font-family: Arial;">&nbsp;</span>
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[&nbsp;<span class="f_Syntax">ELSEIF</span>&nbsp;expression&nbsp;<span class="f_Syntax">THEN</span>&nbsp;]
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<span style="font-family: Arial;">&nbsp;</span>
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[&nbsp;<span class="f_Syntax">ELSE</span>&nbsp;]
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<span style="font-family: Arial;">&nbsp;</span>
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<span class="f_Syntax">END IF</span>
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<span style="font-family: Arial;">&nbsp;</span>
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<span style="font-family: Arial;">&nbsp;</span>
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= <span class="f_Header">Remarks</span> =
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<div style="padding: 0px; margin: 0px 0px 0px 4px;">
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{| width="541" cellspacing="0" cellpadding="1" border="1" style="border: 2px solid rgb(0, 0, 0); border-spacing: 0px; border-collapse: collapse;"
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|- style="vertical-align: top;"
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| valign="top" width="17%" style="width: 88px; border: 1px solid rgb(0, 0, 0);" |
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Expression
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| valign="top" width="100%" style="width: 444px; border: 1px solid rgb(0, 0, 0);" |
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Any expression that evaluates to true or false.
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|}
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</div>
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<span style="font-family: Arial;">&nbsp;</span>
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<span style="font-family: Arial;">&nbsp;</span>
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The one line version of IF can be used&nbsp;:
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IF expression THEN statement [ ELSE statement ]
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The use of [ELSE] is optional.
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<span style="font-family: Arial;">&nbsp;</span>
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Tests like IF THEN can also be used with bits and bit indexes.
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IF var.bit = 1 THEN
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&nbsp; &nbsp; &nbsp; &nbsp;^--- bit is a variable or numeric constant in the range from 0-255
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&nbsp;
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You can use OR or AND to test on multiple conditions. The conditions are evaluated from left to right.
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IF A=1 OR A=2 OR A=3 OR B>10 THEN
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IF A=1 AND A>3 THEN
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&nbsp;
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&nbsp;
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&nbsp;
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Dim Var As Byte, Idx As Byte
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Var = 255
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Idx = 1
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If Var.idx = 1 Then
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&nbsp;Print "Bit 1 is 1"
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EndIf
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<span style="font-family: Arial;">&nbsp;</span>
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<span style="font-family: Arial;">&nbsp;</span>
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= <span class="f_Header">See also</span> =
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[[ELSE]]
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<span style="font-family: Arial;">&nbsp;</span>
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<span style="font-family: Arial;">&nbsp;</span>
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= <span class="f_Header">Example</span> =
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<br/><source lang="bascomavr">
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Dim A As Integer
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A = 10
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If A = 10 Then                                            'test expression
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Print "This part is executed."                          'this will be printed
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Else
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Print "This will never be executed."                    'this not
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End If
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If A = 10 Then Print "New in BASCOM"
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If A = 10 Then Goto Label1 Else print "A<>10"
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Label1:
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Rem The following example shows enhanced use of IF THEN
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If A.15 = 1 Then                                          'test for bit
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Print "BIT 15 IS SET"
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EndIf
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Rem the following example shows the 1 line use of IF THEN [ELSE]
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If A.15 = 0 Then Print "BIT 15 is cleared" Else Print "BIT 15 is set"
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</source><br/>{{Languages}}
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[[Category:BASCOM Language Reference]]

Latest revision as of 00:05, 21 February 2013

Contents

Action

Allows conditional execution or branching, based on the evaluation of a Boolean expression.

 

 

Syntax

IF expression THEN

 

ELSEIF expression THEN ]

 

ELSE ]

 

END IF

 

 

Remarks

Expression

Any expression that evaluates to true or false.

 

 

The one line version of IF can be used :

IF expression THEN statement [ ELSE statement ]

The use of [ELSE] is optional.

 

Tests like IF THEN can also be used with bits and bit indexes.

IF var.bit = 1 THEN

       ^--- bit is a variable or numeric constant in the range from 0-255

 

You can use OR or AND to test on multiple conditions. The conditions are evaluated from left to right.

IF A=1 OR A=2 OR A=3 OR B>10 THEN

IF A=1 AND A>3 THEN

 

 

 

Dim Var As Byte, Idx As Byte

Var = 255

Idx = 1

If Var.idx = 1 Then

 Print "Bit 1 is 1"

EndIf

 

 

See also

ELSE

 

 

Example


Dim A As Integer
A = 10
If A = 10 Then                                             'test expression
Print "This part is executed."                           'this will be printed
Else
Print "This will never be executed."                     'this not
End If
If A = 10 Then Print "New in BASCOM"
If A = 10 Then Goto Label1 Else print "A<>10"
Label1:
 
Rem The following example shows enhanced use of IF THEN
If A.15 = 1 Then                                           'test for bit
Print "BIT 15 IS SET"
EndIf
Rem the following example shows the 1 line use of IF THEN [ELSE]
If A.15 = 0 Then Print "BIT 15 is cleared" Else Print "BIT 15 is set"

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