Ale*_*drH 1 c++ memory pointers
我写了一个简单的程序,它有一个打印变量地址的方法和存储在该地址中的内容,只是为了帮助我更好地理解指针:
#include <iostream>
using std::cout;
using std::endl;
template<typename Type>
void PrintAddressAndContentsOf(Type Variable);
/* Entry point */
int main()
{
int IntegerVariable1 = 5;
int IntegerVariable2 = 6;
double FloatingVariable1 = 10;
double FloatingVariable2 = 11;
PrintAddressAndContentsOf(IntegerVariable1);
PrintAddressAndContentsOf(IntegerVariable2);
PrintAddressAndContentsOf(FloatingVariable1);
PrintAddressAndContentsOf(FloatingVariable2);
}
/* Prints the address and the corresponding contents of a given variable */
template<typename Type>
void PrintAddressAndContentsOf(Type Variable)
{
Type* Pointer = &Variable;
cout << "Address: " << Pointer << endl;
cout << "Contents: " << *Pointer << endl;
}
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当我在Visual Studio上运行它时,我得到以下输出:
Address: 008FFB88
Contents: 5
Address: 008FFB88
Contents: 6
Address: 008FFB84
Contents: 10
Address: 008FFB84
Contents: 11
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如您所见,前两个整数似乎具有相同的008FFB88地址; 同样,两个浮点指针变量具有相同的地址008FFB84.
我的程序中是否存在缺陷,或者我是否缺少一些关键知识来理解这里发生了什么?
这里的问题是你打印的是地址Variable,而不是main的变量地址.地址与Variable您初始化变量的地址无关,并且可以通过多次调用该函数来使用相同的地址.
如果我们改为引用,它给我们一个实际变量的别名,而不是像以下那样的副本:
template<typename Type>
void PrintAddressAndContentsOf(Type& Variable)
{
Type* Pointer = &Variable;
cout << "Address: " << Pointer << endl;
cout << "Contents: " << *Pointer << endl;
}
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Address: 0x7fffc8386ce8
Contents: 5
Address: 0x7fffc8386cec
Contents: 6
Address: 0x7fffc8386cf0
Contents: 10
Address: 0x7fffc8386cf8
Contents: 11
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