string类的实现

来源：互联网发布：linux cp几个文件编辑：程序博客网时间：2024/06/13 15:03
#include<stdio.h>#include <iostream>#include<string.h>using namespace std;class string_my{public:    string_my(const char *str=NULL);//普通构造函数    string_my(const string_my &other);//拷贝构造函数    ~ string_my(void);//析构函数    string_my&  operator=(const string_my &other);//赋值函数    friend ostream & operator<<(ostream& o,const string_my &str);private:    char *m_data;};ostream & operator<<(ostream &o,const string_my &str){    o<<str.m_data;    return o;}string_my::string_my(const char *str){    if(str==NULL)    {        m_data=new char[1];        *m_data='\0';    }    else    {        int length=strlen(str);        m_data=new char[length+1];        strcpy(m_data,str);    }}string_my::~string_my(void){    delete []m_data;}string_my::string_my(const string_my &other){    int length=strlen(other.m_data);    m_data=new char[length+1];    strcpy(m_data,other.m_data);}string_my& string_my::operator=(const string_my &other){    if(this==&other)        return *this;    delete []m_data;    int length=strlen(other.m_data);    m_data=new char[length+1];    strcpy(m_data,other.m_data);    return *this;}int main(){    string_my s("sasa");    cout<<s<<endl;    string_my q("qqqqq");    s=q;    cout<<s<<endl;    s="12123343";    cout<<s<<endl;}
阅读全文
0 0