第 3 章 變數、資料 型別與運算子
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第 3 章 變數、資料 型別與運算子. Ren-Jie Wang, 王 仁 傑 , Ph.D. [email protected] http://rjwang.myweb.hinet.net. 第 3 章 變數、資料 型別與運算子. 3-1 變數與資料 型別的基礎 3-2 變數的命名與宣告 3-3 資料 型別 3-4 運算式與運算子 3-5 資料 型別的轉換. 3-1 變數與資料型別的基礎 - 圖例. 在程式語言的「變數」( Variables )可以視為是一個擁有名稱的盒子,能夠暫時儲存程式執行時所需的資料,如下圖所示:. - PowerPoint PPT PresentationTRANSCRIPT
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3 Ren-Jie Wang, , Ph.D. [email protected] http://rjwang.myweb.hinet.net
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3 3-1 3-2 3-3 3-4 3-5
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3-1 -Variables
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3-2-1 Visual Basic-Visual Basic(VB)"_"16383abcABC.+-*/^
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3-2-1 Visual Basic-Visual Basicdef, no_123, size1, _123, _abc Car, count, height, s1, s2 _ , 123abc
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3-2-1 Visual Basic-3
Boolean
bln
blnDoit
Char
chr
chrA
Integer
int
intCounter
Object
obj
objCar
String
str
strName
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3-2-1 Visual Basic- CamelCasingCamelCasing1/
"_"
MAX_SIZEPI
22
sizeuserName
/
2
pressButtonscrollScreen
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3-2-2 -Visual BasicDimDim volumnvolumnObjectAsDim height, width As Integer2Dim name As String, depth As Integer
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3-2-2 -Dim name As String, depth = 100Dim title As String = "Visual Basic"nametitletitledepth1002008
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3-2-6 Enumeration-EnumerationsEnum/End EnumEnum Color As Integer White = 1 Red Blue = 5 Green Black = GreenEnd Enum
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3-3
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3-3-1 Visual Basic
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3-3-2 -
19
19
&O377
255
&Hff
255
&H3E7
999
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3-3-4 Boolean TypeTrueFalse
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3-3-6 Char TypeUnicodeUnsigned16Visual BasicCharacter LiteralsDim a As Char = "A"C
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3-3-5 String0String LiteralsDim str1 As String = Visual BasicDim str2 As String = Hello World!Dim str3 As String = _ \\localhost\download\joe
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3-3-7 //"#"Dim tday As Date = #12/30/2012 12:00:00 AM#/41224AMPM240
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3-4-3 -f = X^2-2*X+3f = (X+Y)^2+5FahrenheitCelsiusF = (9.0 * C) / 5.0 + 32.0C = (5.0 / 9.0 ) * (F - 32)
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3-4-4 Like-StringVisual Basic
&"abc" & "de" = "abcde"LikeTrueFalse
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3-4-5 "="
=
x = y
N/A
^=
x ^= y
x = x ^ y
+=
x += y
x = x + y
-=
x -= y
x = x - y
*=
x *= y
x = x * y
/=
x /= y
x = x / y
\=
x \= y
x = x \ y
&=
x &= y
x = x & y
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3-5-1 -Implicit Conversions
"250" + 125
375
"250" & 125
"250125"
"250" + "125"
"250125"