vb.net 什么是dim

goodday

Data Type	Size in Bytes	Description	Type
Byte	1	8-bit unsigned integer	System.Byte
Char	2	16-bit Unicode characters	System.Char
Integer	4	32-bit signed integer	System.Int32
Double	8	64-bit floating point variable	System.Double
Long	8	64-bit signed integer	System.Int64
Short	2	16-bit signed integer	System.Int16
Single	4	32-bit floating point variable	System.Single
String	Varies	Non-Numeric Type	System.String
Date	8		System.Date
Boolean	2	Non-Numeric Type	System.Boolean
Object	4	Non-Numeric Type	System.Object
Decimal	16	128-bit floating point variable	System.Decimal

dim 是用来定义 一个 object 或类型

1. Imports System.Console
   
2. Module Module1Sub Main()
   
3. Dim a,b,c as Integer
   
4. 'declaring three variables of type integer
   
5. a=10
   
6. b=20
   
7. c=a+b
   
8. Write("Sum of a and b is" & c)
   
9. End Sub
   
10. 
    
11. End Module

复制代码

[ 本帖最后由 goodday 于 2008-7-19 06:46 PM 编辑 ]

goodday

你要用电脑的资源麻
你要和电脑 申请咯

然后电脑会 发那个空间给你
但你要 讲好你要什么的 空间
如  string , integer , long

如果你要很大的 就申请大的

否则不够 装

dious

請問long是什么呢

goodday

Visual Basic type	Common language runtime type structure	Nominal storage allocation	Value range
Boolean	Boolean	Depends on implementing platform	True or False
Byte	Byte	1 byte	0 through 255 (unsigned)
Char (single character)	Char	2 bytes	0 through 65535 (unsigned)
Date	DateTime	8 bytes	0:00:00 (midnight) on January 1, 0001 through 11:59:59 PM on December 31, 9999
Decimal	Decimal	16 bytes	0 through +/-79,228,162,514,264,337,593,543,950,335 (+/-7.9...E+28) † with no decimal point; 0 through +/-7.9228162514264337593543950335 with 28 places to the right of the decimal; smallest nonzero number is +/-0.0000000000000000000000000001 (+/-1E-28) †
Double (double-precision floating-point)	Double	8 bytes	-1.79769313486231570E+308 through -4.94065645841246544E-324 † for negative values; 4.94065645841246544E-324 through 1.79769313486231570E+308 † for positive values
Integer	Int32	4 bytes	-2,147,483,648 through 2,147,483,647 (signed)
Long (long integer)	Int64	8 bytes	-9,223,372,036,854,775,808 through 9,223,372,036,854,775,807 (9.2...E+18 †) (signed)
Object	Object (class)	4 bytes on 32-bit platform 8 bytes on 64-bit platform	Any type can be stored in a variable of type Object
SByte	SByte	1 byte	-128 through 127 (signed)
Short (short integer)	Int16	2 bytes	-32,768 through 32,767 (signed)
Single (single-precision floating-point)	Single	4 bytes	-3.4028235E+38 through -1.401298E-45 † for negative values; 1.401298E-45 through 3.4028235E+38 † for positive values
String (variable-length)	String (class)	Depends on implementing platform	0 to approximately 2 billion Unicode characters
UInteger	UInt32	4 bytes	0 through 4,294,967,295 (unsigned)
ULong	UInt64	8 bytes	0 through 18,446,744,073,709,551,615 (1.8...E+19 †) (unsigned)
User-Defined (structure)	(inherits from ValueType)	Depends on implementing platform	Each member of the structure has a range determined by its data type and independent of the ranges of the other members
UShort	UInt16	2 bytes	0 through 65,535 (unsigned)

msdn 的 目录

goodday

当我要存

65535 + 1 = 65536 的糖果时

我和电脑 借了 char  的盒子
多了一个 糖果 怎么办？？

会error 咯
那你就要 string 咯

如果你要哦 用

2,147,483,647  +  1000 = 2,147,484,647
integer 肯定  装不下的

那你要用 long  的 9,223,372,036,854,775,807
咯

dious

怎么數字變化那么多
運用hex來算嗎？

goodhermit95

简单来说，数学的代数

1+x=2
Dim x as string

1+x=2
x=textbox1.text
=)

dious

數目怎么可以用String呢

goodday

可以 只是 是当文字来处理
不能 sort 的

dious

不、一個數學運算不可以用stringDe