mfc - 如何在 MFC 中限制文本框中的复制粘贴？

Question

我正在 MFC 中开发一个小应用程序......有一个小问题..希望你们能帮助我解决这个问题......我们开始......问题是......我有 6 个小编辑控件（文本框）在其中我将允许用户输入一些数字..我将字符/文本框的数量限制为 4，但它允许用户复制和粘贴 n 个数字....如何在编辑中限制复制粘贴选项控制....请帮助我...

Answer 1

我找到了两种解决问题的方法....请检查以下内容...

第一种方法：

class CNoPasteEdit: public CEdit
{
public:
CNoPasteEdit();
~CNoPasteEdit();
protected:
// This line will need to be added by hand because WM_PASTE is not available in
// class wizard
afx_msg void OnPaste(WPARAM wParam, LPARAM lParam);
afx_msg void OnContextMenu(CWnd* pWnd, CPoint point);
DECLARE_MESSAGE_MAP()
};

然后你需要像这样编辑这个类的 .cpp 文件

CNoPasteEdit::CNoPasteEdit(){
// Put any construction code here
}

CNoPasteEdit:~:CNoPasteEdit(){
// Put any destruction code here
}

BEGIN_MESSAGE_MAP(CNoPasteEdit, CEdit)
// This line is needed because there is no default macro for WM_PASTE messages
// This line will also need to be added by hand
ON_MESSAGE(WM_PASTE, OnPaste)
ON_WM_CONTEXTMENU()
END_MESSAGE_MAP()

void CNoPasteEdit::OnPaste(WPARAM wParam, LPARAM lParam){
// Put any code here you want to execute when the user right clicks on the edit
// control. Just leave it blank to disable the menu
}

void CNoPasteEdit::OnContextMenu(CWnd* pWnd, CPoint point){
// Put any code here you want to execute when the user tries to paste into the edit
// conrtol. Just leave it blank to prevent pasting.
}

第二种方法： 处理ON_EN_CHANGE事件并捕获 CString 中的文本并检查它是否超过限制字符..如果它..您可以清除带有警告消息的文本框...