Question

我试图创建自己的字符串类，但是当我尝试调试代码的一部分时遇到了问题。当我运行调试器时，它会向我显示一条错误消息“正在使用代码03＆＃39;退出程序”（根据我能够找到的，表示我的系统已运行）的内存），并停止调试器。在调试时我将标记放置在函数的哪个位置并不重要，它只是退出两种方式。但是，如果我只是编译＆amp;运行我遇到的程序没有错误。

这是我遇到困难的两个功能：

void MyString::operator += (const MyString& str)
{
  if(capacity < (size + str.size + 1))
  {
    while(capacity < (size + str.size + 1))
    {
      capacity *= 2;
    }
     char* newData = new char[capacity];
     for (int i = 0; i <= size; ++i)
        newData[i] = data[i];
     delete [] data;
     data = newData;
  }
  strcat(data, str.data);
  size += str.size;
}

MyString MyString::operator + (const MyString& str) const
{
  MyString temp(data);
  if(temp.capacity < (temp.size + str.size + 1))
  {
    while(temp.capacity < (temp.size + str.size + 1))
    {
      temp.capacity *= 2;
    }
     char* newData = new char[temp.capacity];
     for (int i = 0; i <= temp.size; ++i)
        newData[i] = temp.data[i];
     delete [] temp.data;
     temp.data = newData;
  }
  strcat(temp.data, str.data);
  temp.size += str.size;
  return temp;
}

这是我的复制构造函数＆amp;析构函数，如果它有帮助：

MyString::MyString(const MyString& str)
{
  capacity = str.capacity;
  size = str.size;
  data = new char[capacity];
  for(int i = 0; i <= size; ++i)
    data[i] = str.data[i];
}

MyString::~MyString()
{
  delete [] data;
  data = 0;
}

我的代码似乎工作得很好，否则我不一定需要使用调试器来完成它，但我仍然想知道是什么导致调试器以这种奇怪的方式终止。我认为它可能与内存泄漏有关，但我无法弄清楚如何。任何帮助将不胜感激！

编辑：这是类定义：

#ifndef MY_STRING_H
#define MY_STRING_H

#include <iostream>

class MyString
{
  private:
    char* data;
    int capacity;
    int size;

  public:
    MyString();
    MyString(const char*);
    ~MyString();
    MyString(const MyString&);
    MyString operator = (const MyString&);
    bool operator == (const MyString&) const;
    char& operator [ ] (int);
    void operator += (const MyString&);
    MyString operator + (const MyString&) const;
    void getline(istream&, char delimit = ‘\n’);
    int length() const;
    friend std::ostream& operator<< (std::ostream&, MyString&);
};

#endif

和建设者：

MyString::MyString()
{
  size = 0;
  capacity = 2;
  data = new char[capacity];
  data[0] = '\0';
}

MyString::MyString(const char* cStr)
{
  size = 0;
  while(*(cStr + size) != '\0')
  {
    ++size;
  }
  capacity = size + 1;
  data = new char[capacity];
  for(int i = 0; i <= size; ++i)
    data[i] = *(cStr + i);
}

EDIT2：这是主要功能：

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

using namespace std;

int main()
{
  char cStr1[] = {'a','p', 'p', 'l', 'e', '\0'}, cStr2[] = "pie";
  MyString str1(cStr1), str2(cStr2), str3;

  str3 = str2;
  str3 += str1;

  cout << "String 1 of length " << str1.length() << " is: " << endl;
  cout << str1;
  cout << endl;
  cout << "String 2 of length " << str2.length() << " is: " << endl;
  cout << str2;
  cout << endl;
  cout << "String 3 of length " << str3.length() << " is: " << endl;
  cout << str3;
  cout << endl << endl;

  cout << "str1[4] is: " << str1[4] << endl << endl;
  cout << "Does String 1 and String 3 equal eachother?" << endl;
  if(str3 == str1)
    cout << "Yes!" << endl;
  else
    cout << "No." << endl;

  cout << "Does (String 1 + String 2) and String 3 equal eachother?" << endl;
  if(str3 == (str1 + str2))
    cout << "Yes!" << endl;
  else
    cout << "No." << endl;

  cout << "Does (String 2 + String 1) and String 3 equal eachother?" << endl;
  if(str3 == (str2 + str1))
    cout << "Yes!" << endl;
  else
    cout << "No." << endl;

  return 0;
}

EDIT3：以下是其他定义：

MyString MyString::operator = (const MyString& str)
{
  if (this != &str)
  {
    size = str.size;
    capacity = str.capacity;
    char* newData = new char[capacity];
    for (int i = 0; i <= size; ++i)
      newData[i] = str.data[i];
    delete [] data;
    data = newData;
  }
  return *this;
}

bool MyString::operator == (const MyString& str) const
{
   if (size != str.size)
     return false;
   for (int i = 0; i < size; ++i)
   {
     if (data[i] != str.data[i])
       return false;
   }
   return true;
}

char& MyString::operator [ ] (int position)
{
  assert(position >= 0);
  assert(position < size);
  return data[position];
}

int MyString::length() const
{
  return size;
}

ostream& operator<< (ostream& cout, MyString& str)
{
  for(int i = 0; i < str.length(); ++i)
    cout << str[i];
}

C ++ - 使用代码03退出程序

0 个答案: