c - 程序未从文本文件的第一行读取某些字符

Question

因此，在从学生菜单中单击“1”提交作业后，我的程序基本上会要求作业名称/学生姓名。该函数从我的调试文件夹中的文本文件(称为“myassignment.txt”)中读取任意分配。然后它会创建一个名为“submission.txt”的新文件，其中包含作业名称、学生姓名和作业。
当我从学生菜单中单击“2”查看提交的作业时，它可以很好地打印作业名称和学生姓名，但会跳过实际作业第一行的前几个字符。
它会根据作业名称和学生姓名的长度跳过或多或少的字符。
我不明白为什么要这样做。
这是我的数据结构、菜单和菜单前两个选项中使用的函数的代码:

#include "assignmentgrading3.h"

#define MAX_STUDENT_NAME_SIZE 50
#define MAX_ASSIGNMENT_NAME_SIZE 50
#define MAX_ASSIGNMENT_SIZE 1000

typedef struct{
    char assignmentName[MAX_ASSIGNMENT_NAME_SIZE];
    char studentName[MAX_STUDENT_NAME_SIZE];
    char assignment[MAX_ASSIGNMENT_SIZE];
    double score;
} Assignment;

    void studentMenu(Assignment* assignmentStruct) {
        int choice;
        do {
            printf("\nStudent Menu:\n");
            printf("1. Submit an assignment\n");
            printf("2. See the submitted assignment\n");
            printf("3. See the graded assignment\n");
            printf("4. Exit\n");
            printf("Please enter a number from 1 - 4: ");
            scanf("%d", &choice);

            switch (choice) {
                case 1:
                    submitAssignment(assignmentStruct, "myassignment.txt");
                    break;
                case 2:
                    getAssignment(assignmentStruct);
                    displayAssignment(assignmentStruct);
                    break;
                case 3:
                    getGradedAssignment(assignmentStruct);
                    displayGradedAssignment(assignmentStruct);
                    break;
                case 4:
                    exit(0);
                    break;
            }
        } while (choice != 5);
    }

void readRemainingLines(FILE* pFile, char* assignment){
    long charsRead = 0;
    while(fgets(assignment + charsRead, MAX_ASSIGNMENT_SIZE - charsRead, pFile)!= NULL)
    {
        charsRead = strlen(assignment);
        if(charsRead >= MAX_ASSIGNMENT_SIZE - 1)  //Credits: Carl Gelfand
        break;
    }
    assignment[MAX_ASSIGNMENT_SIZE-1] = 0;  //Just to make sure.
}

//Reads the file whose name is provided as string “fileName”, 
//and creates a file named  “submission.txt” as specified in the functional specification. 
//It returns a 1 when it is successful, otherwise it returns a 0. 
int submitAssignment(Assignment* assignmentStruct, char* fileName) {
    FILE* pFile =0;
    //char assignment[MAX_ASSIGNMENT_SIZE];
    char* submissionFileName="submission.txt";

    //Reading information from a user provided file : fileName
    pFile = fopen(fileName,"r");
    if(pFile==NULL){
        printf("%s file did not open\n,",fileName);
        exit(0);
    }//EO if(pFile==NULL)
    printf("Please enter the name of the assignment: ");
    scanf(" %s", assignmentStruct->assignmentName);

    printf("Please enter  your (student) name: ");
    scanf(" %s", assignmentStruct->studentName);
    readRemainingLines(pFile,  assignmentStruct->assignment);
    fclose(pFile);

    // Writing Information to "submission.txt"
    pFile = fopen(submissionFileName, "w");
    if(pFile == NULL) {
        printf("%s file did not open\n,", submissionFileName);
        exit(0);
    } //EO if(pFile==NULL)

    fprintf(pFile, "%s\n", assignmentStruct->assignmentName);
    fprintf(pFile, "%s\n", assignmentStruct->studentName);
    fprintf(pFile, "%s\n", assignmentStruct->assignment);
    fclose(pFile); 
    return 1;
}


int getAssignment(Assignment* assignmentStruct) {
    FILE* pFile = 0;
    pFile = fopen("submission.txt","r");
    if(pFile==NULL){
        printf("file did not open\n,");
        exit(0);
    }
    fscanf(pFile, "%[^\n]", assignmentStruct->assignmentName);
    fscanf(pFile, "%[^\n]", assignmentStruct->studentName);
    readRemainingLines(pFile, assignmentStruct->assignment);
    return 1;
}

void displayAssignment(Assignment* assignmentStruct) {
    char* middleOfAssignment = &(assignmentStruct->assignment[strlen(assignmentStruct->assignmentName) + strlen(assignmentStruct->studentName) + 2]);
    print(assignmentStruct->assignmentName, assignmentStruct->studentName);
    printf("%s \n", middleOfAssignment);
    //printf("%s \n", assignment);
}

void print(char* assignmentName, char* studentName) {
    printf("Assignment Name: %s \nStudent: %s\n", assignmentName, studentName);
}

Answer 1

displayAssignment 在分配 middleOfAssignment 时会跳过分配的前几个字符。它会跳过前一个 strlen(assignmentStruct->assignmentName) + strlen(assignmentStruct->studentName) + 2 个字符。

它应该只打印assignmentStruct->assignment，不需要middleOfAssignment。该代码的唯一原因是如果作业在开头包含作业名称和学生姓名的副本，但事实并非如此。

void displayAssignment(Assignment* assignmentStruct) {
    print(assignmentStruct->assignmentName, assignmentStruct->studentName);
    printf("%s \n", assignmentStruct->assignment);
}