Visual Studio 編譯器錯誤：對委托構造函數的調用應是唯一的成員初始化程序

Question

我有這個程序（如下），它在 Visual Studios 中不斷給我一些編譯器錯誤。 但是當我用 GCC 運行它時，我沒有得到編譯錯誤。 我真的想了解如何在 VS 中進行調試並且遇到了麻煩，因為編譯器錯誤都指向代碼的最后一行。 誰能幫我弄清楚錯誤的含義以及如何解決它們？ 我還有一張 VS 給我的錯誤圖片：

#include <iostream>
#include <vector>
#include <fstream>
#include <string>
using namespace std;

struct Course
{
   string Course;
   int Credit = 0;
   int Score = 0;
   int Grade = 0;
};

struct Student

{
   int ID = 0;
   string Name = "";
   // Course arrCourse[maxCourseAmt];
     vector <Course>Courses;

};

int isInStudVector(vector<Student>vect, int target)
{
   int i = 0;
       while (i <= vect.size())
       {
           if (vect[i].ID == target)
               return i;
           i++;
       }
       return -1;

}



int main()
{
   fstream inputFile;
   string  fileName = "StudentRecords.txt";
   string token;
   //Student arrStu[9];
   vector<Student>Students;

   inputFile.open(fileName, ios::in);

   if (inputFile.is_open())

   {
       int index = 0;
       int ID;
       string Name;
       string CourseName;
       int Credit;
       int Score;

       while (!inputFile.eof())

       {

           inputFile >> ID >> Name >> CourseName >> Credit >> Score;

           int ii = isInStudVector(Students, ID);

           if (ii == -1) // The student record does not exist

           {
               Students.push_back(Student());

               Students[index].ID = ID;

               Students[index].Name = Name;
               Students[index].Courses.push_back(Course());
               Students[index].Courses[0].Course = CourseName;
               Students[index].Courses[0].Credit = Credit;
               Students[index].Courses[0].Score = Score;

               index++;

           }

           else /// The student exists

           {
               /// Add course and score to the existing student record
           }
       }
       inputFile.close();

   }

   else

       cout << "File cannot be opened.";

   return 0;

}

Rebuild started...
1>------ Rebuild All started: Project: hw1, Configuration: Debug Win32 ------
1>hw1.cpp
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(28,14): warning C4018: '<=': signed/unsigned mismatch
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): error C3511: 'Course': a call to a delegating constructor shall be the only member-initializer
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): message : This diagnostic occurred in the compiler generated function 'Course::Course(Course &&)'
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): error C2664: 'Course::Course(const Course &)': cannot convert argument 1 from 'std::string' to 'const Course &'
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): message : Reason: cannot convert from 'std::string' to 'const Course'
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): message : No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(13,1): message : see declaration of 'Course::Course'
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): message : This diagnostic occurred in the compiler generated function 'Course::Course(Course &&)'
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): error C2437: 'Credit': has already been initialized
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): message : This diagnostic occurred in the compiler generated function 'Course::Course(Course &&)'
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): error C2437: 'Score': has already been initialized
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): message : This diagnostic occurred in the compiler generated function 'Course::Course(Course &&)'
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): error C2437: 'Grade': has already been initialized
1>C:\Users\Rob\source\repos\hw1\hw1\hw1.cpp(105,1): message : This diagnostic occurred in the compiler generated function 'Course::Course(Course &&)'
1>Done building project "hw1.vcxproj" -- FAILED.
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

Answer 1

VS 不喜歡struct Course中的成員string Course ，因為“Course”是構造函數的隱含名稱。 重命名成員或結構名稱。

Answer 2

我懷疑您遇到了編譯器錯誤。 GCC 和 Clang 都能正確編譯您的代碼，但不能正確編譯 MSVC 。

但是，修復很簡單。 似乎 MSVC 不喜歡與 class 同名的成員。 只需將Course更改為Name即可：

struct Course
{
   string Name;
   int Credit = 0;
   int Score = 0;
   int Grade = 0;
};