OfArray = VarPtrStringArray ( MyArrayOfStrings() )
'''' gives you the Address of the first element in the Array and First '''' character of this element, ie, Address where "C" is located in '''' Memory
'''' *** How about it, you dont have MIDL compiler? or dont want to go '''' into a process of creating Type Library and Referencing it manually, '''' a simple approach of using StrPtr will be handly enough for you, since '''' this function has the capability of getting the Address of a String, and '''' each element in an Array of Strings is non other than String, so you '''' get the picture clear, you have to point your call to the first element '''' of the Array of String and call
AddressOfArray = StrPtr ( MyArrayOfStrings(0) )
'''' returns the same result as the above call
3] ObjPtr - Returns the Address of an Object
Object Oriented Programming consist of Objects, and these objects also stored into Memory together with all of its properties, as a structured layout, and to obtain its location you need to call ObjPtr Funtion
ex. '''' You want to know where is your Form1 resides in Memory, this '''' Method gives you the Address, in Thread
Dim objMyObject As New Form1
MsgBox "Form1 located at : " & Hex( ObjPtr( objMyObject ) )
Ok, from this point, you are thinking on, How in the world should this Address becomes useful in anyways? well the answer is very clear if you think this way, an Address is a Location in Memory, and your Variables is a Location in Memory with its own Location in Memory, confused? well, to make it simple, you can simply think that this Address is a Location where Datas are stored, and Datas are READABLE and WRITABLE, but you need the Address to have it Written or Read the Data on it, Hmmm, Is Visual Basic Capable of doing these things?
Well, not, if you think plain as in Visual Basic Capability, but APIs are functions that are ready for use by you application, the APIs im blabing about is a RunTime Libararies called RtlMoveMemory and RtlCopyMemory, exported by KERNEL32.DLL.
Aint it charming? First we have found a way to achieve a Memory Address by converting a Variable into a Pointer, Now we have ways to Read and Write to anf from these addresses, but how you may ask? By adding either one of this Declarations to your Application, but not both, since they funtion the same, i suggest use the second one since it supported by all Windows System, while RtlCopyMemory is not.
Private Declare Sub CopyMemory _ Lib "kernel32" Alias _ "RtlCopyMemory" _ (Destination As Any, _ Source As Any, _ ByVal length As Long) '''' RtlCopyMemory copies the contents of one buffer to another.
'''' OR
Private Declare Sub CopyMemory _ Lib "kernel32" Alias _ "RtlMoveMemory" _ (Destination As Any, _ Source As Any, _ ByVal length As Long)
'''' RtlMoveMemory moves memory either forward or backward, aligned or unaligned, '''' in 4-byte blocks, followed by any remaining bytes.
Parameters:
Destination Points to the destination of the move.
Source Points to the memory to be copied.
Length Specifies the number of bytes to be copied.
To make it more easy to Use, Included the File modMemory.bas for Copy and Paste in this Article:
------------cut here------------------------------------------------------------------
Attribute VB_Name = "modMemory" '''' ============================================================================= '''' Copy Memory API '''' ============================================================================= Private Declare Sub CopyMemory _ Lib "kernel32" Alias _ "RtlMoveMemory" _ (Destination As Any, _ Source As Any, _ ByVal length As Long) '''' ============================================================================= '''' Data Sizes '''' ============================================================================= Public Enum e_BinaryData DefineByte = 1 '''' 8 Bits Data DefineWord = 2 '''' 16 Bits Data DefineDoubleWord = 4 '''' 32 Bits Data DefineQuadWord = 8 '''' 64 Bits Data End Enum
'''' ============================================================================= '''' Allows Direct Reading from Memory Pointed by MemPointer '''' with definition of bytes used as in Asm (DB, DW, DD, DX) '''' ============================================================================= Function ReadMem(ByVal MemPointer As Long, _ SizeInBytes As e_BinaryData) Select Case SizeInBytes Case DefineByte Dim DB As Byte CopyMemory DB, ByVal MemPointer, 1 ReadMem = DB Case DefineWord Dim DW As Integer CopyMemory DW, ByVal MemPointer, 2 ReadMem = DW Case DefineDoubleWord Dim DD As Long CopyMemory DD, ByVal MemPointer, 4 ReadMem = DD Case DefineQuadWord Dim DX As Double CopyMemory DX, ByVal MemPointer, 8 ReadMem = DX End Select End Function
'''' ============================================================================= '''' Allows Direct Writing to Memory Pointed by MemPointer '''' with definition of bytes used as in Asm (DB, DW, DD, DX) '''' ============================================================================= Sub WriteMem(ByVal MemPointer As Long, _ SizeInBytes As e_BinaryData, _ ByVal DataToWrite)   上一页 [1] [2] [3] [4] 下一页 [VB.NET程序]通过短信猫发送短信 [C语言系列]使用C#实现ADSL自动拨号 [Web开发]狂人采集器规则使用详解 [电脑技术]windows7快捷键使用大全 [办公软件]PowerPoint模板使用经验之谈 [办公软件]如何在PowerPoint中使用(插入)Media Player控件播… [办公软件]如何在PowerPoint中使用(插入、创建)书签及书签的… [办公软件]如何在PowerPoint中插入(使用)条形码 [办公软件]PowerPoint通过对象播放视频电影 [办公软件]如何通过网页打开PPT
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