richedit设置滚动条的位置和更新内容

大家好，又见面了，我是全栈君

需要txt发现读者richedit的scrollbar位置（为了便于下一次读，直接访问与上次读取下一个读取位置）不值得治疗，采用GetScrollPos、SetScrollPos你可以设置scorllbar位置值。可是！

SetScorllPos调用后仅仅 更新 了scorllbar的位置richedit的内容没得到更新，google一下没有个现成的解决。仅仅得msdn。

WM_VSCROLL 重点标记一下：

However, because the SetScrollInfo SetScrollPos SetScrollRange GetScrollInfo GetScrollPos , and GetScrollRange functions support 32-bit scroll bar position data, there is a way to circumvent the 16-bit barrier of the WM_HSCROLL WM_VSCROLL messages. See GetScrollInfo for a description of the technique.

GetScrollInfo 重点标记一下：

Remarks

The GetScrollInfo function enables applications to use 32-bit scroll positions. Although the messages that indicate scroll bar position, WM_HSCROLL and WM_VSCROLL , provide only 16 bits of position data, the functions SetScrollInfo and GetScrollInfo provide 32 bits of scroll bar position data. Thus, an application can call GetScrollInfo while processing either the WM_HSCROLL or WM_VSCROLL messages to obtain 32-bit scroll bar position data.

To get the 32-bit position of the scroll box (thumb) during a SB_THUMBTRACK request code in a WM_HSCROLL or WM_VSCROLL message, call GetScrollInfo with the SIF_TRACKPOS value in the fMask member of the SCROLLINFO structure. The function returns the tracking position of the scroll box in the nTrackPos member of the SCROLLINFO structure. This allows you to get the position of the scroll box as the user moves it. The following sample code illustrates the technique.

 SCROLLINFO si;
case WM_HSCROLL:
    switch(LOWORD(wparam)) {
        case SB_THUMBTRACK:
          // Initialize SCROLLINFO structure
            ZeroMemory(&si, sizeof(si));
            si.cbSize = sizeof(si);
            si.fMask = SIF_TRACKPOS;
          // Call GetScrollInfo to get current tracking 
          //    position in si.nTrackPos
            if (!GetScrollInfo(hwnd, SB_HORZ, &si) )
                return 1; // GetScrollInfo failed
            break;
    }

实现本文功能：

//保存scrollbar位置
  SCROLLINFO Info={0};
  Info.cbSize=sizeof Info;
  Info.fMask=SIF_TRACKPOS;
  GetScrollInfo(RichEdit1->Handle,SB_VERT,&Info);
  std::auto_ptr<TIniFile> ptrIni(new TIniFile(ExtractFilePath(Application->ExeName)+"Config"));
  ptrIni->WriteInteger("Reader","ScorllPos",Info.nTrackPos);