new placement 的使用

#include <iostream> 

#include "TModel.h" 

int main()
{
    char * p_char=new char[];
    std::cout<<"Source Location = "<<unsigned(p_char)<<std::endl;
    TModel * pTModel;
    pTModel=new (p_char)TModel;
    pTModel->Show();
    delete pTModel; 

    //The Second Part.
    TModel * pTModel2=(TModel *)(new char[sizeof(TModel)]); 

    //If omitted,<Bad Ptr>
    //at    std::cout<<"Location = "<<unsigned(this)
    //  <<" , Name = "<<m_sName
    //  <<std::endl;
    pTModel2=new (pTModel2)TModel; 

    std::cout<<"Source 2 Location = "<<unsigned(pTModel2)<<std::endl;
    pTModel2->Show();
    delete pTModel2; 

    getchar(); 

    return ;
}; 

#include "TModel.h"
#include <iostream> 

void TModel::Show()
{
    std::cout<<"Location = "<<unsigned(this)
        <<" , Name = "<<m_sName
        <<std::endl;
}; 

TModel::TModel()
{
    m_sName="Hello";
}; 

TModel::~TModel()
{ 

};