#include "stdafx.h"
#include "ComboBoxEx.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CAutoComplete

CAutoComplete::CAutoComplete()
{
	m_bAutoComplete = TRUE;
}

CAutoComplete::~CAutoComplete()
{
}


BEGIN_MESSAGE_MAP(CAutoComplete, CComboBox)
	//{{AFX_MSG_MAP(CAutoComplete)
	ON_CONTROL_REFLECT(CBN_EDITUPDATE, OnEditUpdate)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CAutoComplete message handlers

//處理消息循環
BOOL CAutoComplete::PreTranslateMessage(MSG* pMsg)
{
	//捕捉按鍵消息
	if (pMsg->message == WM_KEYDOWN)
	{
		m_bAutoComplete = TRUE;

		int nVirtKey = (int) pMsg->wParam;
		if (nVirtKey == VK_DELETE || nVirtKey == VK_BACK)
			m_bAutoComplete = FALSE;
	}

	return CComboBox::PreTranslateMessage(pMsg);
}

//編輯框更新消息
void CAutoComplete::OnEditUpdate() 
{
  if (!m_bAutoComplete) 
      return;

  //獲得編輯框的字符串
  CString str;
  GetWindowText(str);
  int nLength = str.GetLength();
  
  //當前選擇范圍
  DWORD dwCurSel = GetEditSel();
  WORD dStart = LOWORD(dwCurSel);
  WORD dEnd   = HIWORD(dwCurSel);

  //在列表框中搜索與編輯框中匹配的字符串，然后使其被選擇
  if (SelectString(-1, str) == CB_ERR)
  {
      SetWindowText(str);
      if (dwCurSel != CB_ERR)
        SetEditSel(dStart, dEnd);
  }

  if (dEnd < nLength && dwCurSel != CB_ERR)
      SetEditSel(dStart, dEnd);
  else
      SetEditSel(nLength, -1);
}