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class MySimpleString
{
private:
int m_iSoLuong;
char* m_strChuoiTen;
public:
MySimpleString()
{
m_iSoLuong = 0;
//GG - minor change - avoiding NULL pointers - makes it easier for operator+
m_strChuoiTen = new char[1]; //GG - allocate one byte
m_strChuoiTen[0]=0;//GG-Empty string
}
MySimpleString(const MySimpleString &mssStr)
{
m_iSoLuong = mssStr.m_iSoLuong;
m_strChuoiTen = new char[m_iSoLuong + 1];
strcpy(m_strChuoiTen, mssStr.m_strChuoiTen);
}
MySimpleString(char* ch)
{
m_iSoLuong = strlen(ch);
m_strChuoiTen = new char [m_iSoLuong + 1];
strcpy(m_strChuoiTen, ch);
}
MySimpleString(char ch, int iRepeat)
{
m_iSoLuong = iRepeat;
m_strChuoiTen = new char[iRepeat+1];
strnset(m_strChuoiTen, ch, iRepeat);
m_strChuoiTen[iRepeat] = NULL;
}
~MySimpleString()
{
delete []m_strChuoiTen; //GG
}
void display()
{
printf("\n%d\n%s", m_iSoLuong, m_strChuoiTen);
}
//GG - Added assignment operator
void operator = (const MySimpleString &mss)
{
m_iSoLuong = mss.m_iSoLuong;
delete [] m_strChuoiTen;//GG - Delete current string - prevent memory leak
m_strChuoiTen = new char[m_iSoLuong + 1];
strcpy(m_strChuoiTen, mss.m_strChuoiTen);
}
bool operator == (MySimpleString mss)
{
return (strcmp(m_strChuoiTen, mss.m_strChuoiTen)==0)? true:false;
}
bool operator == (char* ch)
{
return (strcmp(m_strChuoiTen, ch)==0)? true:false;
}
bool operator > (MySimpleString mss)
{
return (strcmp(m_strChuoiTen, mss.m_strChuoiTen)>0)? true:false;
}
bool operator > (char* ch)
{
return (strcmp(m_strChuoiTen, ch)>0)? true:false;
}
bool operator < (MySimpleString mss)
{
return (strcmp(m_strChuoiTen, mss.m_strChuoiTen)<0)? true:false;
}
bool operator < (char* ch)
{
return (strcmp(m_strChuoiTen, ch)<0)? true:false;
}
//GG - Some changes made here
//return type changed to allow chaining of + operator
MySimpleString operator + (const MySimpleString &mss)
{
//in easy steps
MySimpleString mssTemp;
//calculate ne string size
int newSize = m_iSoLuong + mss.m_iSoLuong + 1;
char *temp = new char[newSize];
//copy and cat
strcpy(temp,m_strChuoiTen);
strcat(temp,mss.m_strChuoiTen);
//copy over the particulars
mssTemp.m_strChuoiTen =temp;
mssTemp.m_iSoLuong = newSize-1;
return mssTemp;
}
//GG - Some changes made here
//return type changed to allow chaining of + operator
MySimpleString operator + (char* ch)
{
//in easy steps
MySimpleString mssTemp;
//calculate ne string size
int newSize = m_iSoLuong + strlen(ch) + 1;
char *temp = new char[newSize];
//copy and cat
strcpy(temp,m_strChuoiTen);
strcat(temp,ch);
mssTemp.m_strChuoiTen =temp;
mssTemp.m_iSoLuong = newSize-1;
return mssTemp;
}
};
int main ()
{
MySimpleString mss, mss1;
mss.display();
mss1 = mss+"kiki" + "Dee"; //operator+ and assignment operator test
mss.display(); //check - mss should not have been changed
cout << endl;
mss1.display(); //mss1 should show kikiDee
MySimpleString mss2(mss1);//copy constructor test
mss2.display();
getch();
}
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