【原】CEdit & CRichEdit 使用技巧
作者：lixiaosan
日期：04/07/2006


注：
        m_edit1代表ID為IDC_EDIT1的CEdit控件的control類型的變量
        m_richedit1代表ID為IDC_RICHEDIT1的CRichEditCtrl控件的control類型的變量

---

1.設(shè)置edit只讀屬性

    方法一：
                m_edit1.SetReadOnly(TRUE);
    方法二：
                ::SendMessage(m_edit1.m_hWnd, EM_SETREADONLY, TRUE, 0);

---

2.判斷edit中光標狀態(tài)并得到選中內(nèi)容(richedit同樣適用)

        int nStart, nEnd;
        CString strTemp;

        m_edit1.GetSel(nStart, nEnd);
        if(nStart == nEnd)
        {
            strTemp.Format(_T("光標在%d"), nStart);
            AfxMessageBox(strTemp);
        }
        else
        {
            //得到edit選中的內(nèi)容    
            m_edit1.GetWindowText(strTemp);
            strTemp = strTemp.Mid(nStart) - strTemp.Mid(nEnd);
            AfxMessageBox(strTemp);
        }
    注：GetSel后，如果nStart和nEnd，表明光標處于某個位置（直觀來看就是光標在閃動）；
             如果nStart和nEnd不相等，表明用戶在edit中選中了一段內(nèi)容。

---

3.在edit最后添加字符串

        CString str;
        m_edit1.SetSel(-1, -1);
        m_edit1.ReplaceSel(str);

---

4.隨輸入自動滾動到最后一行(richedit同樣適用)

    方法一：（摘自msdn）
        // The pointer to my edit.
        extern CEdit* pmyEdit;
        int nFirstVisible = pmyEdit->GetFirstVisibleLine();

        // Scroll the edit control so that the first visible line
        // is the first line of text.
        if (nFirstVisible > 0)
        {
            pmyEdit->LineScroll(-nFirstVisible, 0);
        }
    方法二：
        m_richedit.PostMessage(WM_VSCROLL, SB_BOTTOM, 0);

---

5.如何限制edit輸入指定字符

   可以從CEdit派生一個類，添加WM_CHAR消息映射。下面一個例子實現(xiàn)了限定輸入16進制字符的功能。

   void CMyHexEdit::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags) 
   {
        if ( (nChar >= '0' && nChar <= '9') ||
             (nChar >= 'a' && nChar <= 'f') ||
             (nChar >= 'A' && nChar <= 'F') ||
              nChar == VK_BACK || 
              nChar == VK_DELETE)    //msdn的virtual key
       {
            CEdit::OnChar(nChar, nRepCnt, nFlags);
        }     
   }

---

6.如何使用richedit

    添加AfxInitRichEdit();
       CxxxApp::InitInstance()
        {
             AfxInitRichEdit();
          .............
       }

   AfxInitRichEdit()功能：裝載 RichEdit 1.0 Control (RICHED32.DLL).

---

7.如何使用richedit2.0 or richedit3.0

    使用原因：由于RichEdit2.0A自動為寬字符（WideChar），所以它可以解決中文亂碼以及一些漢字問題

    方法一：（msdn上的做法，適用于用VC.NET及以后版本創(chuàng)建的工程）
            To update rich edit controls in existing Visual C++ applications to version 2.0,
            open the .RC file as text, change the class name of each rich edit control from   "RICHEDIT" to  "RichEdit20a".
            Then replace the call to AfxInitRichEdit with AfxInitRichEdit2.
    方法二：以對話框為例：
       (1)    增加一全局變量 HMODULE hMod;
       (2)    在CxxxApp::InitInstance()中添加一句hMod = LoadLibrary(_T("riched20.dll"));
              在CxxxApp::ExitInstance()中添加一句FreeLibrary(hMod);
       (3)      在對話框上放一個richedit，文本方式打開.rc文件修改該richedit控件的類名"RICHEDIT" to  "RichEdit20a".
       (4)      在對話框頭文件添加 CRichEditCtrl m_richedit;
              在OnInitDialog中添加 m_richedit.SubclassDlgItem(IDC_RICHEDIT1, this);

---

8.改變richedit指定區(qū)域的顏色及字體

        CHARFORMAT cf;
        ZeroMemory(&cf, sizeof(CHARFORMAT));
        cf.cbSize = sizeof(CHARFORMAT);
        cf.dwMask = CFM_BOLD | CFM_COLOR | CFM_FACE |
                            CFM_ITALIC | CFM_SIZE | CFM_UNDERLINE;
        cf.dwEffects = 0;
        cf.yHeight = 12*12;//文字高度
        cf.crTextColor = RGB(200, 100, 255); //文字顏色
        strcpy(cf.szFaceName ,_T("隸書"));//設(shè)置字體
    
        m_richedit1.SetSel(1, 5); //設(shè)置處理區(qū)域
        m_richedit1.SetSelectionCharFormat(cf);

---

9.設(shè)置行間距（只適用于richedit2.0）

        PARAFORMAT2 pf;
        pf2.cbSize = sizeof(PARAFORMAT2);
        pf2.dwMask = PFM_LINESPACING | PFM_SPACEAFTER;
        pf2.dyLineSpacing = 200;
        pf2.bLineSpacingRule  = 4;
        m_richedit.SetParaFormat(pf2);

---

10.richedit插入位圖

Q220844：How to insert a bitmap into an RTF document using the RichEdit control in Visual C++ 6.0
http://support.microsoft.com/default.aspx?scid=kb;en-us;220844
http://www.codeguru.com/Cpp/controls/richedit/article.php/c2417/
http://www.codeguru.com/Cpp/controls/richedit/article.php/c5383/

---

11.richedit插入gif動畫

http://www.codeproject.com/richedit/AnimatedEmoticon.asp

---

12.richedit嵌入ole對象

http://support.microsoft.com/kb/141549/en-us

---

13.使richedit選中內(nèi)容只讀

http://www.codeguru.com/cpp/controls/richedit/article.php/c2401/

---

14.打印richedit

http://www.protext.com/MFC/RichEdit3.htm

---

15.richeidt用于聊天消息窗口

http://www.vckbase.com/document/viewdoc/?id=1087
http://www.codeproject.com/richedit/chatrichedit.asp
http://www.codeguru.com/Cpp/controls/richedit/article.php/c2395/

---

16.解決richedit的EN_SETFOCUS和EN_KILLFOCUS無響應(yīng)的問題

http://support.microsoft.com/kb/181664/en-us

---

17.richedit拼寫檢查

http://www.codeproject.com/com/AutoSpellCheck.asp

---

18.改變edit背景色

Q117778：How to change the background color of an MFC edit control
http://support.microsoft.com/kb/117778/en-us

---

19.當edit控件的父窗口屬性是帶標題欄WS_CAPTION和子窗口WS_CHILD時，不能設(shè)置焦點SetFocus

Q230587：PRB: Can't Set Focus to an Edit Control When its Parent Is an Inactive Captioned Child Window
http://support.microsoft.com/kb/230587/en-us

---

20. 在Edit中回車時，會退出對話框 

選中Edit的風格Want Return。

MSDN的解釋如下：
ES_WANTRETURN   Specifies that a carriage return be inserted when the user presses the ENTER key while entering text into a multiple-line edit control in a dialog box. Without this style, pressing the ENTER key has the same effect as pressing the dialog box's default pushbutton. This style has no effect on a single-line edit control.

---

21. 動態(tài)創(chuàng)建的edit沒有邊框的問題

    m_edit.Create(....);
    m_edit.ModifyStyleEx(0, WS_EX_CLIENTEDGE, SWP_DRAWFRAME);

---

22. 一個能顯示RTF，ole（包括gif， wmv，excel ，ppt）的例子

http://www.codeproject.com/richedit/COleRichEditCtrl.asp