lyfz_repos/经典版源码/lyfzClient/branches/708/NumEdit.cpp

// NumEdit.cpp : 实现文件
//

#include "stdafx.h"
#include "NumEdit.h"


// CNumEdit

IMPLEMENT_DYNAMIC(CNumEdit, CEdit)

CNumEdit::CNumEdit()
{
	m_bNegative = FALSE;
	m_bPoint = FALSE;
	m_bZero = FALSE;
}

CNumEdit::~CNumEdit()
{
}

BEGIN_MESSAGE_MAP(CNumEdit, CEdit)
	ON_WM_CHAR()
END_MESSAGE_MAP()


// CNumEdit 消息处理程序
void CNumEdit::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags)
{
	// 获取插入符在客户区的坐标值;
	POINT caret;
	::GetCaretPos(&caret);	
	// 根据插入符位置获取最近的字符索引（插入符的前一个字符位置）;
	caret.x = LOWORD(CharFromPos(caret));

	CString strEdit;
	GetWindowText(strEdit);

	if (nChar == VK_BACK && strEdit.GetLength()) //退格键;
	{
		// 是否删除了小数点或负号;
		if ( caret.x && strEdit[caret.x-1] == _T('.') )
			m_bPoint = FALSE;

		if ( caret.x && strEdit[caret.x-1] == _T('-') )
			m_bNegative = FALSE;

		CEdit::OnChar(nChar, nRepCnt, nFlags);
	}

	if (isdigit(nChar)) 
	{
		// 判断是否已有负号,若字符在负号前,退出;
		if ( m_bNegative && caret.x == 0 )
			return;

		if ( m_bNegative )
		{
			if ( m_bZero && caret.x == 2 && nChar == _T('0'))
				return;
		}
		else
		{
			if ( !m_bPoint && m_bZero && caret.x == 1 && nChar == _T('0'))
				return;
		}

		if ( m_bNegative )
		{	
			if (caret.x == 1 && nChar == _T('0'))
			{
				m_bZero = TRUE;
			}
		}
		else
		{// 负号后面最多只有一个0,且0后面紧接着的是'.'
			if (caret.x == 0 && nChar == _T('0'))
			{
				m_bZero = TRUE;
			}
		}

		CEdit::OnChar(nChar, nRepCnt, nFlags);
	}
	else if (nChar == '-' && !m_bNegative)
	{// 负号只能在第一位;
		if (0 != caret.x)
			return;

		m_bNegative = TRUE;
		CEdit::OnChar(nChar, nRepCnt, nFlags);
	}
	else if (nChar == '.' && !m_bPoint)
	{
		if ( m_bNegative && caret.x == 1)
		{// 小数点不能在负号后面,即第二个字符索引;
			return;
		}
		m_bPoint = TRUE;
		CEdit::OnChar(nChar, nRepCnt, nFlags);
	}
}

BOOL CNumEdit::PreTranslateMessage(MSG* pMsg)
{
	// TODO: 在此添加专用代码和/或调用基类
	if ( pMsg->message == WM_LBUTTONUP )
	{
		CString strEdit;
		GetWindowText(strEdit);

		int nStart, nEnd;
		GetSel(nStart, nEnd);
		if ( nEnd > nStart) // 不区选字符;
		{
			printf("有区选光标\n");
			SetSel(-1,strEdit.GetLength());
		}
	}
	else if ( pMsg->message == WM_KEYDOWN )
	{
		if ( pMsg->wParam == VK_DELETE )
		{
			POINT caret;
			::GetCaretPos(&caret);	
			// 根据插入符位置获取最近的字符索引（插入符的前一个字符位置）;
			LONG nPos  = LOWORD(CharFromPos(caret));
			printf("NumEdit,%d,%d\t 插入符最近的字符位置：%d\n", caret.x, caret.y, nPos);

			CString strEdit;
			GetWindowText(strEdit);

			if (strEdit.GetLength())
			{
				// 是否删除了小数点或负号;
				if ( strEdit.GetAt(nPos) == _T('.') )
					m_bPoint = FALSE;

				if ( strEdit.GetAt(nPos) == _T('-') )
					m_bNegative = FALSE;
			}
		}
	}

	return CEdit::PreTranslateMessage(pMsg);
}