c++ - 无法使用 ifstream 打开文件

Question

我想获得有关以下代码行的一些帮助。对于函数 constructArray，我无法运行它，正如 !aFile as true 消息所示，但我不知道错误是什么。非常感谢您的帮助另外，如何使用 .txt 创建 inFile 文件名，我尝试使用 +".txt"进行缩进，但由于参数中的文件类型，我无法这样做。编译器运行图像:https://imgur.com/a/wkGwL

    using namespace std;

    enum NumType {Odd, Even};

    struct Number
    {
         int no;
         NumType type;
         int oddDigits;
         int evenDigits;
         int sumDigits;
         int noDigits;
    };

    // Create inFile data file with certain number of integers which are randomly generated
    void constructInfile (fstream& aFile, char fileName[]);


    // Read data from infile txt file and transfer to array of numbers
    int constructArray (fstream& aFile,const char fileName[], Number ran[]);

    /*
    void processArray (Number [ ], int);

    // Transfer information from array and store into output file called outfile txt with specific information format
    void arrayToOutfile (fstream&, char [ ], Number [ ], int);
    */


    const int MAX = 50;

    int main()
    {
    srand(time(NULL));
    fstream aFile;
    char fileName [MAX];

    cout << "Enter designated file name to be created" << endl;
    cin >> fileName;

    constructInfile (aFile,fileName);

    Number ran[MAX];
    int recNo = constructArray(aFile,fileName,ran);
    cout << recNo << " of records transferred" << endl;

    }

    // Create inFile data file with certain number of integers which are randomly generated
    void constructInfile (fstream& aFile,char fileName[]){
        aFile.open(fileName, ios::out);

        if(aFile.fail()){
            cout << "File open unsuccessful" << endl;
            aFile.close();
            exit(1);
        }

        cout << "Begin creation of " << fileName << " file" << endl << endl;

        int size = rand()%51+50;

        for(int a = 0;a < size;a++){
            aFile << rand()%1000+1 << endl;
        }

        cout << fileName << " file successfully created" << endl;

    }


    // Read data from infile txt file and transfer to array of numbers
    int constructArray (fstream& aFile,const char fileName[], Number ran[]){

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

        if (!aFile)
        {
            cout << fileName << " failed to open" << endl;
            aFile.close ();

            return 0;
        }

        cout << "Begin from " << fileName << " to array" << endl;

        int i = 0;

        char tabKey;

        while (aFile >> ran[i].no)
        {
            aFile.get (tabKey);     // read and discard
            i++;
        }

        aFile.close ();
        cout << fileName << " to array done" << endl;

        return i;
    }

Answer 1

您在 ios::out 模式下打开了一个文件并且从未关闭过它!

您再次尝试在 ios::in 模式下打开同一个文件。如何在不正确关闭 fstream 的情况下以两种不同的模式打开文件两次？

您需要在函数 constructInfile() 中关闭文件流!!!