二维指针的new和delete
下面的这个类是与数据库相关的,但这个类会出现内存泄露,不知道怎么修改,对指针的理解不太深刻,忘各位能帮个忙,帮小弟修改一下,最好来点注释...
ClassDataSet.h

C/C++ code

#include "stdafx.h"#include <tchar.h>#include <string>using namespace std;#ifndef ClassDataSet__H_H#define ClassDataSet__H_Hclass ClassDataSet{private :    string **value;    long NumCol;    long NumRow;public:    ClassDataSet();    void ClearValue();    void InitialValue(long TotalRow,long TotalCol);    void InputVaule(string v,long EachRow,long EachCol);    long RowCount();    long ColCount();    string ReValue(long SelectRow,long SelectCol);};#endif

ClassDataSet.cpp

C/C++ code

#include"ClassDataSet.h"#include <stdlib.h>using namespace std;ClassDataSet::ClassDataSet(){    this->NumCol=0;    this->NumRow=0;}long ClassDataSet::RowCount(){    return this->NumRow;}long ClassDataSet::ColCount(){    return this->NumCol;}void ClassDataSet::InitialValue(long TotalRow,long TotalCol){    const long rowTemp=TotalRow;    const long colTemp=TotalCol;    this->value=new string*[rowTemp];//new 了之后没有在析构函数当中delete,不知如何修改这个类.    for(long k=0;k<rowTemp;++k)    {        this->value[k]=new string[colTemp];    }    this->NumRow=TotalRow;    this->NumCol=TotalCol;}void ClassDataSet::InputVaule(string v,long CurrentRow,long CurrentCol){    this->value[CurrentRow][CurrentCol]=v;}string ClassDataSet::ReValue(long CurrentRow,long CurrentCol){    if(CurrentRow>=this->NumRow||CurrentCol>=this->NumCol)    {        return "Overflow";    }    else    {        return this->value[CurrentRow][CurrentCol];    }}void ClassDataSet::ClearValue(){    this->value=new string*[0];    this->value[0]=new string[0];    this->NumCol=0;    this->NumRow=0;    delete[] *this->value;}

在另一个类中定义了类型为ClassDataSet的一个成员变量

C/C++ code

class MyControlSqlServer//连接数据库类 连接之前需要打开 {public:    MyControlSqlServer(_bstr_t SqlCon);//构造函数，配置数据库    ClassDataSet Select(_bstr_t Action);//Select语句    bool WriteDatebase(_bstr_t Action);//Insert,Update,delete,create语句    bool Open();    _ConnectionPtr m_pConnection;//连接方式    _RecordsetPtr m_pRecordset;//虚拟表    void close();    //bool Update(_bstr_t Action);//Update语句private:    _bstr_t strConnect;    ClassDataSet obj;};

C/C++ code

ClassDataSet MyControlSqlServer::Select(_bstr_t Action){    try    {        _variant_t temp;        if(m_pConnection==NULL)        {            this->obj.ClearValue();            return this->obj;//链接不上        }        _bstr_t bstrSQL(Action);        m_pRecordset.CreateInstance(__uuidof(Recordset));         // 取得表中的记录        m_pRecordset->Open(bstrSQL,m_pConnection.GetInterfacePtr(),adOpenDynamic,adLockOptimistic,adCmdText);        long ColCount=m_pRecordset->GetFields()->Count;//获得一条记录的字段数，列总数FieldsPtr        long RowCount=0;//行总数        while(!m_pRecordset->adoEOF)//用循环获得行总数        {            RowCount++;            m_pRecordset->MoveNext();///移到下一条记录        }        this->obj.InitialValue(RowCount,ColCount);        m_pRecordset->MoveFirst();        long CurrentRow=0;        long CurrentCol=0;        while(!m_pRecordset->adoEOF)        {            for(long CurrentCol=0;CurrentCol<ColCount;++CurrentCol)            {                temp=m_pRecordset->GetCollect((long)CurrentCol);///取得第i列的值,从0开始计数，                string a;                if(temp.vt==1)                    a="NULL";                else                    a=(_bstr_t)temp;                this->obj.InputVaule(a,CurrentRow,CurrentCol);            }            m_pRecordset->MoveNext();///移到下一条记录            ++CurrentRow;        }        return this->obj;    }    catch(_com_error e)    {        //cout<<(string)(_bstr_t)e.Description()<<endl;        this->obj.ClearValue();        return this->obj;    }} 
 

使用的时候
MyControlSqlServer dbmanger;
dbmanger.Select();
在调试窗口提示内存泄露.

[解决办法]
二维指针的new和delete
New:
A** ga = new A*[m];
for(int i = 0; i < m; i++)
{
ga[i] = new A[n];
}

Delete:
for(int i = 0; i < m; i++)
{
delete []ga[i];
}
delete []ga;

应此

C/C++ code

void ClassDataSet::ClearValue(){    for(long k=0;k<NumRow;++k)    {        delete[] this->value[k];    }    delete[] this->value;    this->NumCol=0;    this->NumRow=0;}
[解决办法]
按LS的改，另外你可能还得写拷贝构造函数和operator=。
[解决办法]
先MARK..
[解决办法]
探讨

二维指针的new和delete
New:
A** ga = new A*[m];
for(int i = 0; i < m; i++)
{
 ga[i] = new A[n];
}

Delete:
for(int i = 0; i < m; i++)
{
 delete []ga[i];
}
delete []ga;

应此

C/C++ code
voi……

[解决办法]
好像没见到 析构函数。 开了空间没释放吧。
[解决办法]
C/C++ code
ClassDataSet::~ClassDataSet(){  for(long k=0;k<NumRow;++k)    {        delete[] this->value[k];    }    delete[] this->value;    this->NumCol=0;    this->NumRow=0;}