Incompatibility using managed array and std:array at same time

问题

I have my C++/CLI code using arrays like this (for example):

array<String^>^ GetColNames() { 
    vector<string> vec = impl->getColNames();
    array<String^>^ arr = gcnew array<String^>(vec.size());

    for (int i = 0; i < vec.size(); i++) { 
        arr[i] = strConvert(vec[i]); 
    }
    return arr; 
}

It's compiling fine until I add the library "array" to the project:

#include <array>

Then I don't know how to use the managed CLI array, because the compiler thinks that all the declared arrays are the std::array.

Errors examples:

array<String^>^ arr
//           ^ Error here: "too few arguments for class template "std::array""

gcnew array<String^>(vec.size())
//    ^ Error: "Expected a type specifier"

How to solve this? I tried removing using namespace std from that file, but it makes no difference. Should I remove that from every other C++ file on the project?

回答1:

Clearly you have a using namespace std; in scope somewhere. Watch out for it being used in .h file if you cannot find it.

You can resolve the ambiguity, the C++/CLI extension keywords like array are in the cli namespace. This compiles fine:

#include "stdafx.h"
#include <array>

using namespace std;         // <=== Uh-oh
using namespace System;

int main(cli::array<System::String ^> ^args)
{
    auto arr = gcnew cli::array<String^>(42);
    return 0;
}

来源：https://stackoverflow.com/questions/23062179/incompatibility-using-managed-array-and-stdarray-at-same-time