-- 发布时间：4/13/2005 11:18:00 AM
-- [求助] xml读写时候内存释放问题
小弟写了一个类，使用MSXML4.dll来操作xml文件，但是在完成我想完成的操作后，点cancel按钮关闭对话框时，windows报错，经检查，发现是在l该类的析构函数处出现内存访问错误。 我把这个类贴出来，把报错内容贴出来，那位大牛给俺瞅瞅，要崩溃了都T_T
//-----------------------------------------------头文件-------------------------------------------------------
// XmlAccess.h: interface for the CXmlAccess class.
//
//////////////////////////////////////////////////////////////////////
#if !defined(AFX_XMLACCESS_H__CB244AB8_79D3_43A6_BE98_E0A642D182C3__INCLUDED_)
#define AFX_XMLACCESS_H__CB244AB8_79D3_43A6_BE98_E0A642D182C3__INCLUDED_
#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000
#include "stdafx.h"
#import "msxml4.dll"
#include <atlbase.h> // Includes CComVariant and CComBSTR.
class CXmlAccess
{
public:
CXmlAccess();
virtual ~CXmlAccess();
HRESULT XmlFileOperateInit(CString strFileName);
void SaveFile(CString strFileName);
void release();
HRESULT getElementValue (CComBSTR bstrNodeName,CComVariant &varNodeValue);
HRESULT setElementValue (CComBSTR bstrNodeName ,CComVariant varNodeValue);
protected:
private:
MSXML2::IXMLDOMElementPtr rootNode;
MSXML2::IXMLDOMDocumentPtr pDoc;
};
#endif // !defined(AFX_XMLACCESS_H__CB244AB8_79D3_43A6_BE98_E0A642D182C3__INCLUDED_)
//--------------------------------------------。cpp-----------------------------------------------------------
// XmlAccess.cpp: implementation of the CXmlAccess class.
//
//////////////////////////////////////////////////////////////////////
#include "stdafx.h"
#include "CXmlFileClassTry.h"
#include "XmlAccess.h"
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
CXmlAccess::CXmlAccess()
{
}
CXmlAccess::~CXmlAccess()
{
//rootNode->Release();
//pDoc->Release();
}
//文件读写的初始化，获取文件指针和根节点以备下面的函数使用
HRESULT CXmlAccess::XmlFileOperateInit(CString strFileName)
{
HRESULT hr = pDoc.CreateInstance(__uuidof(MSXML2::DOMDocument30));
if(!SUCCEEDED(hr))
{
// MessageBox("无法创建DOMDocument对象，请检查是否安装了MS XML Parser 运行库!");
}
//加载文件
pDoc->load((CComVariant)strFileName);
//获取根节点
pDoc->get_documentElement(&rootNode);
// rootNode->Release();
// pDoc->Release();
// return 0;
return hr;
}
HRESULT CXmlAccess::getElementValue (CComBSTR bstrNodeName,CComVariant &varNodeValue)
{
MSXML2::IXMLDOMElementPtr pXMLNode2=NULL;
// MSXML2::IXMLDOMNodeListPtr nodeList2;//nodeList2 二级节点，nodeLsit3三级节点
MSXML2::IXMLDOMNodeListPtr pXMLNodeList;
pXMLNodeList= rootNode->getElementsByTagName((BSTR)bstrNodeName);
//if (FAILED(hr)) MessageBox("get_nodeTypedValue");
// BSTR var;
// VARIANT varVal;
// long nCount ;
long lCount2;
// Retrieve total number of nodes in the list.
HRESULT hr = pXMLNodeList->get_length(&lCount2);
if (lCount2<1)
{
//MessageBox("notfound");
}
else{
// MessageBox("found,Name And Attribute Followed Next");
for (int i = 0; i < lCount2; i++)
{
pXMLNode2 = pXMLNodeList->nextNode();
// VARIANT varValue;
hr= pXMLNode2 ->get_nodeTypedValue(&varNodeValue);
if (!FAILED(hr))
{
return 0;
}
else return 1;
} //end for i
} //endif
//release
// pXMLNode2->Release();
// nodeList2->Release();
//pXMLNodeList->Release();
}
HRESULT CXmlAccess::setElementValue (CComBSTR bstrNodeName ,CComVariant varNodeValue)
{
BOOL replaced=0;
MSXML2::IXMLDOMElementPtr pXMLNode2=NULL;
// MSXML2::IXMLDOMNodeListPtr nodeList2;//nodeList2 二级节点，nodeLsit3三级节点
MSXML2::IXMLDOMNodeListPtr pXMLNodeList;
pXMLNodeList= rootNode->getElementsByTagName((BSTR)bstrNodeName);
// BSTR var;
// VARIANT varVal;
// long nCount ;
long lCount2;
// Retrieve total number of nodes in the list.
HRESULT hr = pXMLNodeList->get_length(&lCount2);
if (lCount2<1)
{
}
else
{
for (int i = 0; i < lCount2; i++)
{
pXMLNode2 = pXMLNodeList->nextNode();
//修改节点值
hr = pXMLNode2 ->put_nodeTypedValue(varNodeValue);
if (FAILED(hr)) replaced=0 ; else replaced=1;
} //end for i
} //end else
//pXMLNode2->Release();
// nodeList2->Release();//
//pXMLNodeList->Release();
return replaced;
}
void CXmlAccess::SaveFile(CString strFileName)
{
pDoc->save((CComVariant)strFileName);
// pDoc->Release;
// rootNode->Release;
}
void CXmlAccess::release()
{
if(rootNode!=NULL) rootNode->Release();
if(pDoc!=NULL) pDoc->Release();
}
//---------------------------------------------------错误---------------------------------------------------
First-chance exception in CXmlFileClassTry.exe: 0xC0000005: Access Violation.
//-----------------------------------下面是comip.h文件里的错误
// Releases only if the interface is not null.
// The interface is not set to NULL.
//
void _Release() throw()
{
if (m_pInterface != NULL) {
//·￥￥￥￥￥￥￥￥￥这里出错
错误-------------〉〉 m_pInterface->Release();
//·￥￥￥￥￥￥￥￥￥这里出错
}
}
求救阿