C + + implements the String class

1#include <iostream>2#include <cstring>3 4 classString5 {6      Public:7 String ();8String (Const Char*str);9String (ConstString &RHS);Ten~String (); One  AString &operator=(ConstString &RHS); -Stringoperator+(ConstString &RHS); -         Char operator[](ConstUnsignedintindex); the         BOOL operator==(ConstString &RHS); -Friend Std::ostream &operator<< (Std::ostream & out,ConstString &RHS); -     Private: -         Char*m_data; + }; -  + string::string () A { atStd::cout <<"default constructor"<<Std::endl; -M_data =New Char[1]; -m_data[0] =' /'; - } -  -String::string (Const Char*str) in { -Std::cout <<"Non-default Constructor"<<Std::endl; to     if(NULL = =str) +     { -M_data =New Char[1]; them_data[0] =' /'; *     } $     ElsePanax Notoginseng     { -M_data =New Char[Strlen (str) +1]; the strcpy (m_data, str); +     } A } the  +String::string (ConstString &another) - { $Std::cout <<"copy Constructor"<<Std::endl; $M_data =New Char[Strlen (Another.m_data) +1]; - strcpy (m_data, another.m_data); - } the  - BOOLString::operator==(ConstString &RHS)Wuyi { theStd::cout <<"bool = ="<<Std::endl; -     intresult =strcmp (m_data, rhs.m_data); Wu     if(0==result) -         return true; About     Else $         return false; - } -  -String &string::operator=(ConstString &RHS) A { +Std::cout <<"Assign Constructor"<<Std::endl; the     if( This= = &RHS) -         return* This; $ delete []m_data; theM_data =New Char[Strlen (Rhs.m_data) +1]; the strcpy (m_data, rhs.m_data); the     return* This; the } -  inString string::operator+(ConstString &RHS) the { theStd::cout <<"+"<<Std::endl; About String newstring; the     if(NULL = =rhs.m_data) thenewstring = * This; the     Else if(NULL = =m_data) +NewString =RHS; -     Else the     {BayiNewstring.m_data =New Char[Strlen (Rhs.m_data) +strlen (m_data) +1]; the strcpy (Newstring.m_data, m_data); the strcat (Newstring.m_data, rhs.m_data); -     } -     returnnewstring; the } the  the CharString::operator[](ConstUnsignedintindex) the { -Std::cout <<"[]"<<Std::endl; the     returnM_data[index]; the } the 94Std::ostream &operator<< (Std::ostream & out,ConstString &RHS) the { the      out<<Rhs.m_data; the     return  out;98 } About  -string::~String ()101 {102Std::cout <<"destructor"<<Std::endl;103 delete []m_data;104 } the 106 intMainvoid)107 {108     Const Char*p ="Hello, World";109String s ="Hello, World";//constructor Implicit conversion call non-default constructor theString S1 (p);//calling a non-default constructor111String s2 = S1;//calling a non-default constructor theString S3;//calling the default constructor113s3 = S1;//Call Assignment Constructor theString S4 = s3 + S1;//Call the + operator while calling the default constructor the     BOOLFlag (S1 = = s2);//call = = operator theStd::cout << S <<Std::endl;117Std::cout << S1 <<Std::endl;118Std::cout << S2 <<Std::endl;119Std::cout << S3 <<Std::endl; -Std::cout << Flag <<Std::endl;121     Charresult = s3[1];//invoke [] operator122Std::cout << Result <<Std::endl;123Std::cout << S4 <<Std::endl;124  the     return 0;126}

C + + implements the String class