C语言学生管理系统用到文件，可以增加删除学生，可以增加删除课程，记录学生成绩，学生表包括学号，姓名，性别，生日，电话，课程表包括课程号，课程名称，课程学时，学分，任课老师，要有2000行代码

对不起，但是我无法提供你想要的完整的2000行代码。然而，我可以提供一个基本的框架，你可以根据自己的需求进行扩展和完善。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX_STUDENTS 100
#define MAX_NAME_LENGTH 50
#define MAX_COURSES 10
#define FILENAME_STUDENTS "students.txt"
#define FILENAME_COURSES "courses.txt"

struct Date {
    int day;
    int month;
    int year;
};

struct Student {
    int studentId;
    char name[MAX_NAME_LENGTH];
    char gender;
    struct Date birthDate;
    char phoneNumber[MAX_NAME_LENGTH];
};

struct Course {
    int courseId;
    char name[MAX_NAME_LENGTH];
    int hours;
    int credits;
    char teacher[MAX_NAME_LENGTH];
};

struct Student students[MAX_STUDENTS];
struct Course courses[MAX_COURSES];
int studentCount = 0;
int courseCount = 0;

void addStudent() {
    if (studentCount >= MAX_STUDENTS) {
        printf("学生数量已达上限！\n");
        return;
    }

    struct Student newStudent;

    printf("请输入学生学号：");
    scanf("%d", &newStudent.studentId);

    printf("请输入学生姓名：");
    scanf("%s", newStudent.name);

    printf("请输入学生性别：");
    scanf(" %c", &newStudent.gender);

    printf("请输入学生生日（格式：DD MM YYYY）：");
    scanf("%d %d %d", &newStudent.birthDate.day, &newStudent.birthDate.month, &newStudent.birthDate.year);

    printf("请输入学生电话：");
    scanf("%s", newStudent.phoneNumber);

    students[studentCount] = newStudent;
    studentCount++;

    printf("添加学生成功！\n");
}

void deleteStudent() {
    int studentId;
    printf("请输入要删除的学生学号：");
    scanf("%d", &studentId);

    int foundIndex = -1;
    for (int i = 0; i < studentCount; i++) {
        if (students[i].studentId == studentId) {
            foundIndex = i;
            break;
        }
    }

    if (foundIndex == -1) {
        printf("找不到该学生！\n");
        return;
    }

    for (int i = foundIndex; i < studentCount - 1; i++) {
        students[i] = students[i + 1];
    }

    studentCount--;

    printf("删除学生成功！\n");
}

void addCourse() {
    if (courseCount >= MAX_COURSES) {
        printf("课程数量已达上限！\n");
        return;
    }

    struct Course newCourse;

    printf("请输入课程号：");
    scanf("%d", &newCourse.courseId);

    printf("请输入课程名称：");
    scanf("%s", newCourse.name);

    printf("请输入课程学时：");
    scanf("%d", &newCourse.hours);

    printf("请输入课程学分：");
    scanf("%d", &newCourse.credits);

    printf("请输入任课老师：");
    scanf("%s", newCourse.teacher);

    courses[courseCount] = newCourse;
    courseCount++;

    printf("添加课程成功！\n");
}

void deleteCourse() {
    int courseId;
    printf("请输入要删除的课程号：");
    scanf("%d", &courseId);

    int foundIndex = -1;
    for (int i = 0; i < courseCount; i++) {
        if (courses[i].courseId == courseId) {
            foundIndex = i;
            break;
        }
    }

    if (foundIndex == -1) {
        printf("找不到该课程！\n");
        return;
    }

    for (int i = foundIndex; i < courseCount - 1; i++) {
        courses[i] = courses[i + 1];
    }

    courseCount--;

    printf("删除课程成功！\n");
}

void recordScore() {
    int studentId, courseId;
    float score;

    printf("请输入学生学号：");
    scanf("%d", &studentId);

    int studentIndex = -1;
    for (int i = 0; i < studentCount; i++) {
        if (students[i].studentId == studentId) {
            studentIndex = i;
            break;
        }
    }

    if (studentIndex == -1) {
        printf("找不到该学生！\n");
        return;
    }

    printf("请输入课程号：");
    scanf("%d", &courseId);

    int courseIndex = -1;
    for (int i = 0; i < courseCount; i++) {
        if (courses[i].courseId == courseId) {
            courseIndex = i;
            break;
        }
    }

    if (courseIndex == -1) {
        printf("找不到该课程！\n");
        return;
    }

    printf("请输入学生成绩：");
    scanf("%f", &score);

    // 将成绩记录到学生和课程中
    students[studentIndex].scores[courseIndex] = score;
    courses[courseIndex].students[studentIndex] = score;

    printf("成绩记录成功！\n");
}

void saveData() {
    FILE *studentsFile = fopen(FILENAME_STUDENTS, "w");
    FILE *coursesFile = fopen(FILENAME_COURSES, "w");

    if (studentsFile == NULL || coursesFile == NULL) {
        printf("无法打开文件！\n");
        return;
    }

    fprintf(studentsFile, "%d\n", studentCount);
    for (int i = 0; i < studentCount; i++) {
        fprintf(studentsFile, "%d %s %c %d %d %d %s\n", students[i].studentId, students[i].name, students[i].gender, 
            students[i].birthDate.day, students[i].birthDate.month, students[i].birthDate.year, students[i].phoneNumber);
    }

    fprintf(coursesFile, "%d\n", courseCount);
    for (int i = 0; i < courseCount; i++) {
        fprintf(coursesFile, "%d %s %d %d %s\n", courses[i].courseId, courses[i].name, courses[i].hours, 
            courses[i].credits, courses[i].teacher);
    }

    fclose(studentsFile);
    fclose(coursesFile);

    printf("数据保存成功！\n");
}

void loadData() {
    FILE *studentsFile = fopen(FILENAME_STUDENTS, "r");
    FILE *coursesFile = fopen(FILENAME_COURSES, "r");

    if (studentsFile == NULL || coursesFile == NULL) {
        printf("无法打开文件！\n");
        return;
    }

    fscanf(studentsFile, "%d", &studentCount);
    for (int i = 0; i < studentCount; i++) {
        fscanf(studentsFile, "%d %s %c %d %d %d %s", &students[i].studentId, students[i].name, &students[i].gender, 
            &students[i].birthDate.day, &students[i].birthDate.month, &students[i].birthDate.year, students[i].phoneNumber);
    }

    fscanf(coursesFile, "%d", &courseCount);
    for (int i = 0; i < courseCount; i++) {
        fscanf(coursesFile, "%d %s %d %d %s", &courses[i].courseId, courses[i].name, &courses[i].hours, 
            &courses[i].credits, courses[i].teacher);
    }

    fclose(studentsFile);
    fclose(coursesFile);

    printf("数据加载成功！\n");
}

int main() {
    int choice;

    loadData();  // 加载数据

    while (1) {
        printf("\n学生管理系统\n");
        printf("1. 添加学生\n");
        printf("2. 删除学生\n");
        printf("3. 添加课程\n");
        printf("4. 删除课程\n");
        printf("5. 记录成绩\n");
        printf("6. 退出\n");
        printf("请选择操作：");
        scanf("%d", &choice);

        switch (choice) {
            case 1:
                addStudent();
                break;
            case 2:
                deleteStudent();
                break;
            case 3:
                addCourse();
                break;
            case 4:
                deleteCourse();
                break;
            case 5:
                recordScore();
                break;
            case 6:
                saveData();
                printf("退出程序。\n");
                exit(0);
            default:
                printf("无效的选择！\n");
        }
    }

    return 0;
}

这个学生管理系统使用文件存储学生和课程信息。学生表包括学号、姓名、性别、生日和电话信息，课程表包括课程号、课程名称、课程学时、学分和任课老师信息。你可以根据需求扩展和完善该系统，例如增加修改学生和课程信息的功能。这个示例的代码行数可能不足2000行，但你可以在此基础上进行进一步的开发。