Question

我想知道是否有人可以看看为什么我在这里遇到运行时错误。

Project1.exe中0x6FBDEBC2（msvcr110d.dll）的第一次机会异常： 0xC0000005：访问冲突写入位置0x7CB67DEB。未处理 Project1.exe中的0x6FBDEBC2（msvcr110d.dll）异常：0xC0000005：访问冲突写入位置0x7CB67DEB。

#include <iostream>
#include <string>
#include <sstream>

using namespace std;

int main(){
    struct person {
        string name;
        int age;
        int weight;
        string nickname;
    } ;

    person people[1];

    for(int i = 0; i < sizeof(people); i++){
        string s[4];
        for(int x = 0; x < 4; x++){
            cout << "Please enter person " << i << "'s " << (x == 0 ? "name" : x == 1 ? "age" : x == 2 ? "weight" : x == 3 ? "nickname" : "unknown") << "." << endl;
            getline(cin, s[x]);
        }
        people[i].name = s[0];
        stringstream(s[1]) >> people[i].age;
        stringstream(s[2]) >> people[i].weight;
        people[i].nickname = s[3];
    }

    for(int i = 0; i < sizeof(people); i++)
        cout << "Person " << i << ": name = " << people[i].name << ", age = " << people[i].age << ", weight = " << people[i].weight << ", nickname = " << people[i].nickname << endl; 

    cout << "Please press enter to continue.";
    fflush(stdin);
    cin.clear();
    cin.get();
}

它可以正常运行，直到第二个for循环，它似乎运行错误。

Answer 1

你的问题在于：

sizeof(people)

这不会给出people数组的长度，而是给出数组的总大小（以字节为单位）。您可以使用std::begin(people)和std::end(people)来获取迭代器到数组的开头和结尾。

for (auto it = std::begin(people); it != std::end(people); ++it)
{
  // it is an iterator to an element of people
  it->name = ....;
}

或者，您可以使用基于范围的循环：

for (auto& p : people)
{
  // p is a reference to an element of people here
  p.name = ....;
}

Answer 2

要防止出现此类问题，请考虑使用此方法，该方法允许您存储静态数组的大小：

int ARRAY_SIZE = 1;
person people[ARRAY_SIZE];

然后你的for循环：

for(int i = 0; i < ARRAY_SIZE; i++)

测试结构和数组时出现msvcr110d.dll！memcpy错误

2 个答案: