vb動態(tài)加載dll的一個類-實(shí)現(xiàn)vb動態(tài)加載dll并動態(tài)調(diào)用dll導(dǎo)出的函數(shù)的一個方便辦法

vb動態(tài)加載dll的一個類,實(shí)現(xiàn)vb動態(tài)加載dll并動態(tài)調(diào)用dll導(dǎo)出的函數(shù)的一個方便辦法自從會vb用調(diào)用動態(tài)庫函數(shù)以來,我一直在想:如何動態(tài)的調(diào)用dll里的函數(shù)?網(wǎng)上有一個用CallWindowProc函數(shù)的方法,不過我還是喜歡自己有個辦法.今天工夫不負(fù)有心人,我終于把我心中一直想的辦法給實(shí)現(xiàn)了,干脆就往自己的空間上貼吧.錯誤的地方,希望可以得到有這方面的師傅給以指正,以求進(jìn)步!對于系統(tǒng)api我沒有嘗試,如果調(diào)用約定相符,應(yīng)該適用于對系統(tǒng)api的調(diào)用.我自己用c寫個dll,然后在vb里寫了這個類.以下代碼只是我簡單的實(shí)現(xiàn),主要的是看實(shí)現(xiàn)的道理.vc代碼:///'我把dll文件名命名為:dll#include<Windows.h>#include<stdlib.h>#include<string.h>#include'stdafx.h'BOOLAPIENTRYDllMain(HANDLEhModule,DWORD

ul_reason_for_call,LPVOIDlpReserved){returnTRUE;}extern'C'BOOL_declspec(dllexport)add(inta){MessageBoxA(NULL,'運(yùn)行在dll里!','成功',MB_OK);a=999;return1;}///vb代碼:'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''類代碼:Private狀態(tài)標(biāo)志AsBooleanPrivate模塊句柄AsLongPrivate本地函數(shù)地址備份(0To4)AsBytePrivate被替換函數(shù)的地址AsLongPublicFunction替換函數(shù)地址(模塊名AsString,函數(shù)名AsString,本地函數(shù)地址AsLong)AsBoolean

If0=本地函數(shù)地址Then替換函數(shù)地址=0ExitFunctionEndIf

被替換函數(shù)的地址=替換函數(shù)地址Dim函數(shù)地址AsLongDimaAsLongDim跳轉(zhuǎn)指令(0To4)AsByte

'加載模塊模塊句柄=LoadLibrary(模塊名)If0<>模塊句柄Then'狀態(tài)標(biāo)志=1Else:替換函數(shù)地址=0ExitFunctionEndIf'檢索函數(shù)地址函數(shù)地址=GetProcAddress(ByVal模塊句柄,ByVal函數(shù)名)If0<>函數(shù)地址Then'狀態(tài)標(biāo)志=1Else替換函數(shù)地址=0ExitFunctionEndIf'計(jì)算跳轉(zhuǎn)地址a=函數(shù)地址-(本地函數(shù)地址+5)'構(gòu)造跳轉(zhuǎn)地址跳轉(zhuǎn)指令(0)=233a=WriteProcessMemory(-1,ByValVarPtr(跳轉(zhuǎn)指令(1)),ByValVarPtr(a),4,0)If0=aThen替換函數(shù)地址=0ExitFunctionEndIf'先備份本地函數(shù)入口指令a=WriteProcessMemory(-1,ByValVarPtr(本地函數(shù)地址備份(0)),ByVal本地函數(shù)地址,5,0)If0=aThen替換函數(shù)地址=0ExitFunctionEndIf'寫入跳轉(zhuǎn)指令a=WriteProcessMemory(-1,ByVal本地函數(shù)地址,ByValVarPtr(跳轉(zhuǎn)指令(0)),5,0)If0=aThen替換函數(shù)地址=0ExitFunctionElse:狀態(tài)標(biāo)志=1替換函數(shù)地址=1EndIfEndFunctionPublicFunction還原函數(shù)地址()AsBooleanIf0=狀態(tài)標(biāo)志Then還原函數(shù)地址=0ExitFunctionEndIfDimaAsLonga=WriteProcessMemory(-1,ByVal被替換函數(shù)的地址,ByValVarPtr(本地函數(shù)地址備份(0)),5,0)If0=aThen還原函數(shù)地址=0ExitFunctionElse:狀態(tài)標(biāo)志=0還原函數(shù)地址=1EndIfFreeLibrary模塊句柄EndFunctionPublicFunction當(dāng)前狀態(tài)()AsBoolean當(dāng)前狀態(tài)=狀態(tài)標(biāo)志EndFunction''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''vb普通模塊代碼:'讀寫內(nèi)存的api函數(shù)PublicDeclareFunctionWriteProcessMemoryLib'kernel32'(ByValhProcessAsLong,ByVal_lpBaseAddressAsAny,lpBufferAsAny,ByValnSizeAsLong,lpNumberOfBytesWrittenAsLong)AsLong'加載模塊的api函數(shù)PublicDeclareFunctionLoadLibraryLib'kernel32'Alias'LoadLibraryA'(ByVallpLibFileNameAsString)AsLong'檢索模塊里函數(shù)地址的api函數(shù)PublicDeclareFunctionGetProcAddressLib'kernel32'(ByValhModuleAsLong,ByVallpProcNameAsString)AsLong'PublicDeclareFunctionFreeLibraryLib'kernel32'(ByValhLibModuleAsLong)AsLong'模擬一個函數(shù)與dll里,我們想調(diào)用函數(shù)類型和參數(shù)一致,用類將函數(shù)的地址替換PublicFunction測試函數(shù)(參數(shù)AsLong)AsBoolean'我們隨便給返回0,因?yàn)檫@個指令將不會被程序執(zhí)行到測試函數(shù)=0EndFunction''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''vb窗口模塊代碼:PrivateSubForm_Load()Dim模塊名AsString,函數(shù)名AsString模塊名=App.Path+'/dll.dll''模塊名現(xiàn)在可以自己定了,自由了!函數(shù)名='add'DimpAsBooleanDimaaAsNewClass1p=aa.替換函數(shù)地址(模塊