C++自定义"List"实现不起作用

很多问题：

1. 构造函数应初始化所有成员
2. 未实现三条规则(在拥有的指针上(
3. 可怕的间距(您需要更好地格式化代码(
4. 所有数组内存分配都是错误的

分配：

template <class T>
void RList<T>::AllocateNew(T obj)
{
    if (this->m_Length == 0)
    {
        // This will not work as you have not allocated the area for ListObjects.
        // I don't think this is a special case. You should have allocated a zero
        // length array in the constructor then then else part would have worked
        // like normal when adding the first element.
        this->ListObject[0] = obj;
    }
    else
    {
        // OK good start
        T* NewListObject = new T [this->m_Length + 1];
        // Rather than do this manually there is std::copy
        for (unsigned int x = 0; x < this->m_Length; x++)
        {
            NewListObject[x] = this->ListObject[x];
        }
        NewListObject[this->m_Length] = obj;
       // Though unlikely there is a posability of an exception from a destructor.
       // So rather than call delete on a member you should swap the member and the
       // temporary. Then when the object is a good state you can delete the old one.
       delete [] ListObject;
       this->ListObject = NewListObject;
       // Definately do NOT do this.
       // as you have just stored this pointer into ListObject.
       // ListObject is now pointing at free'ed memory.
       delete [] NewListObject;    
       // So I would have done (for the last section
       //   std::swap(this->ListObject, NewListObject);
       //   ++this->m_Length;
       //   // now we delete the old data
       //   delete [] NewListObject; // (remember we swapped above)
    }
}

RemoveIndex

template <class T>
void RList<T>::RemoveIndex(unsigned int N)
{
    T* NewListObject = new T [this->m_Length - 1];
    for (int x = 0; x < this->m_Length -1; x++)
    {
        if (x != N)
        {
            // You need to compensate for the fact that you removed one
            // element (otherwise you have a hole in your new array).
            NewListObject[x] = this->ListObject[x];
        }
    }
    // Same comment as above.
    // Do not call delete on a member.
    // Make sure the object is a good state before doing dangerous stuff.
    delete [] ListObject;
    this->ListObject = NewListObject;
}

if (this->m_Length == 0)
{
    this->ListObject[0] = obj;
}

您必须先分配ListObject，然后才能执行此操作。

注意：你的实现有很多问题，你应该把它发布到代码评审中，或者查看一本书，看看如何实现一个合适的向量。

您遇到了很多问题，但这个问题肯定会使您的程序崩溃：

(在AllocateNew结束时(：

this->ListObject = NewListObject;
delete [] NewListObject;

现在，this->ListObject指向已释放的内存。

你能告诉我哪里完全错了吗？

您正在重新设计STL矢量类。您可以围绕它编写一个thin-wrapper来提供您想要的API，但使用类as-is可能更容易。您的示例如下：

#include <iostream>
#include <vector>
using namespace std;
int main( )
{
  vector< int > Numbers;
  Numbers.push_back( 5 );
  Numbers.push_back( 100 );
  Numbers.push_back( 1500 );
  for ( unsigned int x = 0; x < Numbers.size( ); x++ )
  {
    cout << Numbers[x] << endl;
  }
  cin.get();
  return 0;
}