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#pragma once// CSearchEditclass CSearchEdit : public CEdit{	DECLARE_DYNAMIC(CSearchEdit)public:	CSearchEdit();	virtual ~CSearchEdit();public:    void ShowTip();    const CString GetTip()const { return m_strTip; }private:    const CString m_strTip = _T("搜索图片");protected:	DECLARE_MESSAGE_MAP()    afx_msg void OnEnKillfocus();    afx_msg void OnEnSetfocus();    afx_msg HBRUSH CtlColor(CDC* pDC, UINT nCtlColor);};

// SearchEdit.cpp : 实现文件//#include "stdafx.h"#include "TestDlg.h"#include "SearchEdit.h"// CSearchEditIMPLEMENT_DYNAMIC(CSearchEdit, CEdit)CSearchEdit::CSearchEdit(){}CSearchEdit::~CSearchEdit(){}void CSearchEdit::ShowTip(){    SetWindowText(m_strTip);}BEGIN_MESSAGE_MAP(CSearchEdit, CEdit)    ON_CONTROL_REFLECT(EN_KILLFOCUS, &CSearchEdit::OnEnKillfocus)    ON_CONTROL_REFLECT(EN_SETFOCUS, &CSearchEdit::OnEnSetfocus)    ON_WM_CTLCOLOR_REFLECT()END_MESSAGE_MAP()// CSearchEdit 消息处理程序void CSearchEdit::OnEnKillfocus(){    CString str;    GetWindowText(str);    if (str == _T(""))    {        SetWindowText(m_strTip);    }}void CSearchEdit::OnEnSetfocus(){    CString str;    GetWindowText(str);    if (str == m_strTip)    {        SetWindowText(_T(""));    }}HBRUSH CSearchEdit::CtlColor(CDC* pDC, UINT nCtlColor){    // TODO:  在此更改 DC 的任何特性    CString str;    GetWindowText(str);    if (str == m_strTip)    {        pDC->SetTextColor(RGB(192, 192, 192));        return (HBRUSH)GetStockObject(WHITE_BRUSH);    }    // TODO:  如果不应调用父级的处理程序，则返回非 null 画笔    return NULL;}

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