my-playlist/MyString.cpp at main · mateea326/my-playlist · GitHub

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

int MyString::strlen(const char *s)
{
    if (!s) return 0;
    int i = 0;
    while (*s != '\0')
        i++, s++;
    return i;
}

MyString::MyString()
{
    str = new char[1];
    str[0] = '\0';
}

MyString::MyString(const char *str2)
{
    if (str2)
    {
        int length = strlen(str2);
        str = new char[length + 1];
        for (int i = 0; i < length; i++)
            str[i] = str2[i];
        str[length] = '\0';
    }
    else
    {
        str = new char[1];
        str[0] = '\0';
    }
}

MyString::MyString(const MyString &s)
{
    int length = strlen(s.str);
    str = new char[length + 1];
    for (int i = 0; i < length; i++)
        str[i] = s.str[i];
    str[length] = '\0';
}

MyString::~MyString()
{
    delete[] str;
}

void MyString::operator=(const MyString &s)
{
    if (this == &s) return;
    delete[] str;
    int length = strlen(s.str);
    str = new char[length + 1];
    for (int i = 0; i < length; i++)
        str[i] = s.str[i];
    str[length] = '\0';
}

void MyString::add_ch(char new_ch)
{
    int length = strlen(str);
    char *str2 = new char[length + 2];
    for (int i = 0; i < length; i++)
        str2[i] = str[i];
    str2[length] = new_ch;
    str2[length + 1] = '\0';
    delete[] str;
    str = str2;
}

void MyString::strcat(const char *str2)
{
    if (!str2) return;
    int length = strlen(str);
    int length2 = strlen(str2);
    char *str3 = new char[length + length2 + 1];
    for (int i = 0; i < length; i++)
        str3[i] = str[i];
    for (int i = 0; i < length2; i++)
        str3[length + i] = str2[i];
    str3[length + length2] = '\0';
    delete[] str;
    str = str3;
}

MyString::operator const char *() const
{
    return str;
}

std::ostream &operator<<(std::ostream &out, const MyString &s)
{
    if (s.str) out << s.str;
    return out;
}

std::istream &operator>>(std::istream &in, MyString &s)
{
    char buffer[1024];
    if (in.getline(buffer, 1024))
    {
        delete[] s.str;
        int length = s.strlen(buffer);
        s.str = new char[length + 1];
        for (int i = 0; i < length; i++)
            s.str[i] = buffer[i];
        s.str[length] = '\0';
    }
    return in;
}