delphi7

Question

function NewWriteFile(hFile: THandle;const Buffer;nNumberOfBytesToWrite: DWORD;
   var lpNumberOfBytesWritten: DWORD;lpOverlapped: POverlapped): BOOL;stdcall;
type
  TWriteFile=function(hFile: THandle;const Buffer;nNumberOfBytesToWrite: DWORD;
   var lpNumberOfBytesWritten: DWORD;lpOverlapped: POverlapped): BOOL;stdcall;
begin
   result:=TWriteFile(hook[1].OldFunction)(hFile,Buffer,nNumberOfBytesToWrite,lpNumberOfBytesWritten,lpOverlapped);
   if hFile=pShMem^.FileHandle then
      SaveForWriteFile(buffer,nNumberOfBytesToWrite);  //????  lpNumberOfBytesWritten);
end;不用解释代码的意思，我就想问问这种定义结构有什么用处，谢谢

Answer 1

从OldFunction取得原始WriteFile函数的地址，然后调用之！
当然你也可以不用定义TWriteFile类型，不过就要使用basm来调用原始WriteFile了。