Question

我很难完成这段代码。

#include (sorry but it won't show up the #include such as stdio.h AND OTHERS) But this is not the problem.


using namespace std;


struct CustomerFile {
    int arrivalTime;

    string driverfName,
        driverlName,
        typeOfDriver,
        driverLicNumber,
        vehicleMake,
        vehicleModel,
        Lot_taken,
        vehicleRegNumber,
        attendantName,
        ParkingArea,
        Comments,
        checkOutDateTime,
        checkInDateTime;
};

int arrivalTime;

string driverfName,

    driverlName,
    typeOfDriver,
    driverLicNumber,
    vehicleMake,
    vehicleModel,
    Lot_taken,
    vehicleRegNumber,
    attendantName,
    ParkingArea,
    Comments,
    checkOutDateTime,
    checkInDateTime;

int main(int argc, char * * argv) {

    FILE * cfPtr;

    if ((cfPtr = fopen("CustomerFile.dat", "rb+")) == NULL) {
        printf("file could not be opened");
    } else {
        printf("\nFile is Written to");
        printf("\nFile is open");

        printf("\n\n\nEnter Vehicle Registration Number: ");
        scanf("%s", & CustomerFile.vehicleRegNumber);

        while (CustomerFile.vehicleRegNumber != 0) /*#IF THE USER does not enter 0 the loops should begin, but there is a problem here*/
        {

            printf("\nFirst Name: ");
            fscanf("%s", CustomerFile.driverfName); /*here is the problem, I think is had something to do with the struct name*/
            printf("\nLast Name:  ");
            printf("\nType of Driver:  ");
            printf("\nDriver's License Number:  ");
            printf("\nVehicle Make:  ");
            printf("\nVehicle Model:   ");
            printf("\nComments   ");
            printf("\nParking SpaceTaken ");

            printf("\n\nenter firstname, lastname");
            fscanf(stdin, "%s%s%s%s%s%s%s%s1f", CustomerFile.driverfName I think this has something to do with the statement * /
                                CustomerFile.driverlName   / * okay here * /
                                CustomerFile.typeOfDriver       / * okay here * /
                                CustomerFile.driverLicNumber         / * okay here * /
                                CustomerFile.vehicleMake      / * okay here * /
                                CustomerFile.vehicleModel       / * okay here * /
                                CustomerFile.Comments       / * okay here * /
                                &CustomerFile.Lot_taken);       / * okay here * /


                        fwrite( sizeof(struct CustomerFile ), 1, cfPtr);




                }
                        fclose( cfPtr);
                }


return 0;

}

好的问题是它不断给出错误; *

File.cpp：144：错误：在'。'标记
之前预期的primary-expression
File.cpp：148：错误：在'。'标记
之前预期的primary-expression
File.cpp：162：错误：在'。'标记
之前的预期primary-expression
File.cpp：172：错误：无效转换为'unsigned int'到'const void *'

File.cpp：172：错误：从“FILE *”到“size_t”的转换无效   /usr/include/stdio.h:708：错误：函数'size_t fwrite（const void *，size_t，size_t，FILE *）'的参数太少   File.cpp：172：错误：此时在文件中

我相信或者读到它有一个事实，即C ++编译器不适用于c99。如果是这样，那你如何在c ++中使用结构？我知道你只使用一个结构，例如CustomerFile.driverlName，然而，编译器继续拒绝它。我也遇到了while循环问题。我熟悉c和c ++，我们学习了c和c ++，代码用c ++编写，但教科书给出的c代码不能在c ++编译器中运行。

Answer 1

CustomerFile是一个类，因此当您尝试从其中访问数据成员时它将无法工作，就像它是实例一样。要创建实例，请执行：

CustomerFile file;

并将Customer.的所有实例替换为file.，它应该可以解决错误。

Answer 2

您定义了数据类型CustomerFile。要使用已定义的结构CustomerFile，您需要创建一个对象并使用它。例如：

CustomerFile  customer; 
customer.vehicleModel = "ABC";

vehicleRegNumber的类型为字符串而不是整数，将其与此{/ 1>} 0进行比较

while (customer.vehicleRegNumber != "0" )

在变量名之间添加,

  fscanf( stdin, "%s%s%s%s%s%s%s%s1f", customer.driverfName, customer.driverlName ,

fscanf()函数是一个C函数，它不知道std::string（或类）。所以你使用了像这样的临时字符串

      char temp[100];
      printf("\nFirst Name: ");
      fscanf(stdin, "%99s", temp );
      customer.driverfName = temp;

File.cpp：148：错误：在'。'之前预期的primary-expression令牌不同符号

2 个答案: