4.4
4.4.5.
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VB Boolean. , L:
Dim L As Boolean |
L : True False. 0 False, 1. ,
Dim f As Double = 6.8 L = CBool(f) ' L = True f=0 L = CBool(f) ' L = False |
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() . 4.4.2-1.
4.4.2-1
= | |
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>= | |
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4.4.2-2 .
4.4.2-2
5 < 10 | True, 5 10 |
5 > 10 | False, 5 10 |
7 <> 3 | True, 7 3 |
X > 45 | True, X 45; False |
TextBox1.Text="Stop" | True, "Stop"; False |
5 - 1 > 1 + 2 | True, 5-1 (4), 1+2 (3) , 4 > 3, .. 4 3 |
X >= y + z | True, X y z; False |
, , .., .
, , , . 4.4.2-3 .
, Not 7 < 9 False,
4 > 3 And 7 < 9 True.
.4.4.2-4 ( ). T (True) , F (False) .
(. .3-5.3-8) .
VB : If, If Select Case.
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4.4.2-3
Not | True False False True |
And | , |
Or | , |
Xor | , |
4.4.2-4
Not x | X And y | X Or y | x Xor y | ||
X | Y | ||||
T | T | F | T | T | F |
T | F | F | F | T | T |
F | T | T | F | T | T |
F | F | T | F | F | F |
If :
If L Then () [Else () ] |
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If:
If x > 0 Then y = Sqrt(x) Else y = 1 If d=>10 Then epsilon = 0.001 If lambda < 1 Or beta = 3 Then lambda = beta: x = 0 If x < 10 Then y = 1 Else If x < 100 Then y = 2 Else y = 4 |
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If L1 Then [ __1 ] [ElseIf L2 Then [ __2 ]... Else [ __n ] ] End If |
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If ElseIf.
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If:
If x>0 Then y =Sqrt(x) z=1+y p=4 End If | If x < 10 Then y=1 Else y=2 z=4 End If |
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4.4.2-1. /, .
vvodDbl1()
ViodDbl1() Double , vvodSng3() vivodSng3() Single vvodInt4() vivodInt4() Integer .
vvodDbl1(), vivodDbl1(), vvodSng3() vivodSng3() 4.4.3, vvodInt4() vivodInt4() . 4.4.2-1 4.4.2-2.
'-Function Integer ' TextBox Function vvodInt4(ByVal T As TextBox) As Integer Return CInt(T.Text) End Function |
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. 4.4.2-1. Integer TextBox
'-Sub Integer TextBox Sub vivodInt4(ByVal Z As Integer, ByVal T As TextBox) T.Text = CStr(Z) End Sub |
. 4.4.2-2. Integer TextBox