用c语言写一份完整的学生信息管理系统 要求： （1）数据结构：创建学生信息结点类型以及学生信息结构体； （2）存储结构：选择单链表存储学生信息。 （3）实现功能（以函数方式实现）：学生信息链表创建、学生信息输入、学生信息查询、学生信息修改、学生信息删除、学生信息输出（全部或部分输出）或保存到文件，学生相关排序。

好的，以下是一份使用C语言编写的学生信息管理系统，具体实现了您提出的要求：

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

typedef struct student_info {
    int id;
    char name[20];
    int age;
    struct student_info *next;
} StudentInfo;

StudentInfo *create_student_info(int id, char name[], int age) {
    StudentInfo *new_student_info = (StudentInfo *)malloc(sizeof(StudentInfo));
    new_student_info->id = id;
    strcpy(new_student_info->name, name);
    new_student_info->age = age;
    new_student_info->next = NULL;
    return new_student_info;
}

StudentInfo *add_student_info(StudentInfo *head, StudentInfo *new_student_info) {
    if (head == NULL) {
        head = new_student_info;
    } else {
        StudentInfo *current = head;
        while (current->next != NULL) {
            current = current->next;
        }
        current->next = new_student_info;
    }
    return head;
}

void print_student_info(StudentInfo *student_info) {
    printf("%d\t%s\t%d\n", student_info->id, student_info->name, student_info->age);
}

void print_all_student_info(StudentInfo *head) {
    StudentInfo *current = head;
    printf("ID\tName\tAge\n");
    while (current != NULL) {
        print_student_info(current);
        current = current->next;
    }
}

StudentInfo *find_student_info(StudentInfo *head, int id) {
    StudentInfo *current = head;
    while (current != NULL) {
        if (current->id == id) {
            return current;
        }
        current = current->next;
    }
    return NULL;
}

StudentInfo *delete_student_info(StudentInfo *head, int id) {
    StudentInfo *current = head;
    if (current == NULL) {
        printf("There is no student information to delete.\n");
        return NULL;
    }
    if (current->id == id) {
        head = current->next;
        free(current);
        printf("Delete student information with ID %d successfully.\n", id);
        return head;
    }
    while (current->next != NULL) {
        if (current->next->id == id) {
            StudentInfo *temp = current->next;
            current->next = temp->next;
            free(temp);
            printf("Delete student information with ID %d successfully.\n", id);
            return head;
        }
        current = current->next;
    }
    printf("There is no student information with ID %d.\n", id);
    return head;
}

void modify_student_info(StudentInfo *student_info) {
    printf("Please enter the new information of the student:\n");
    printf("ID: ");
    scanf("%d", &student_info->id);
    printf("Name: ");
    scanf("%s", student_info->name);
    printf("Age: ");
    scanf("%d", &student_info->age);
}

int compare_by_id(StudentInfo *a, StudentInfo *b) {
    return a->id - b->id;
}

int compare_by_name(StudentInfo *a, StudentInfo *b) {
    return strcmp(a->name, b->name);
}

void sort_student_info(StudentInfo *head, int (*compare)(StudentInfo *a, StudentInfo *b)) {
    int flag = 1;
    while (flag) {
        flag = 0;
        StudentInfo *current = head;
        while (current->next != NULL) {
            if (compare(current, current->next) > 0) {
                StudentInfo *temp = create_student_info(current->id, current->name, current->age);
                modify_student_info(current);
                modify_student_info(current->next);
                temp->id = current->id;
                strcpy(temp->name, current->name);
                temp->age = current->age;
                current->id = current->next->id;
                strcpy(current->name, current->next->name);
                current->age = current->next->age;
                current->next->id = temp->id;
                strcpy(current->next->name, temp->name);
                current->next->age = temp->age;
                flag = 1;
                free(temp);
            }
            current = current->next;
        }
    }
}

void save_student_info_to_file(StudentInfo *head, char *filename) {
    FILE *fp = fopen(filename, "w");
    if (fp == NULL) {
        printf("Failed to open file %s.\n", filename);
        return;
    }
    StudentInfo *current = head;
    while (current != NULL) {
        fprintf(fp, "%d %s %d\n", current->id, current->name, current->age);
        current = current->next;
    }
    fclose(fp);
    printf("Save student information to file %s successfully.\n", filename);
}

StudentInfo *load_student_info_from_file(StudentInfo *head, char *filename) {
    FILE *fp = fopen(filename, "r");
    if (fp == NULL) {
        printf("Failed to open file %s.\n", filename);
        return head;
    }
    int id, age;
    char name[20];
    while (fscanf(fp, "%d %s %d", &id, name, &age) != EOF) {
        StudentInfo *new_student_info = create_student_info(id, name, age);
        head = add_student_info(head, new_student_info);
    }
    fclose(fp);
    printf("Load student information from file %s successfully.\n", filename);
    return head;
}

int main() {
    StudentInfo *head = NULL;
    while (1) {
        printf("Please select the function you want to perform:\n");
        printf("1. Create student information\n");
        printf("2. Input student information\n");
        printf("3. Query student information\n");
        printf("4. Modify student information\n");
        printf("5. Delete student information\n");
        printf("6. Output student information\n");
        printf("7. Save student information to file\n");
        printf("8. Load student information from file\n");
        printf("9. Sort student information by ID\n");
        printf("10. Sort student information by name\n");
        printf("0. Exit\n");
        int choice;
        scanf("%d", &choice);
        switch (choice) {
            case 0:
                printf("Exit successfully.\n");
                return 0;
            case 1: {
                int id, age;
                char name[20];
                printf("Please enter the student information:\n");
                printf("ID: ");
                scanf("%d", &id);
                printf("Name: ");
                scanf("%s", name);
                printf("Age: ");
                scanf("%d", &age);
                StudentInfo *new_student_info = create_student_info(id, name, age);
                head = add_student_info(head, new_student_info);
                printf("Create student information successfully.\n");
                break;
            }
            case 2: {
                int id, age;
                char name[20];
                printf("Please enter the student information:\n");
                printf("ID: ");
                scanf("%d", &id);
                printf("Name: ");
                scanf("%s", name);
                printf("Age: ");
                scanf("%d", &age);
                StudentInfo *new_student_info = create_student_info(id, name, age);
                head = add_student_info(head, new_student_info);
                printf("Input student information successfully.\n");
                break;
            }
            case 3: {
                int id;
                printf("Please enter the ID of the student to be queried: ");
                scanf("%d", &id);
                StudentInfo *student_info = find_student_info(head, id);
                if (student_info == NULL) {
                    printf("There is no student information with ID %d.\n", id);
                } else {
                    print_student_info(student_info);
                }
                break;
            }
            case 4: {
                int id;
                printf("Please enter the ID of the student to be modified: ");
                scanf("%d", &id);
                StudentInfo *student_info = find_student_info(head, id);
                if (student_info == NULL) {
                    printf("There is no student information with ID %d.\n", id);
                } else {
                    modify_student_info(student_info);
                    printf("Modify student information with ID %d successfully.\n", id);
                }
                break;
            }
            case 5: {
                int id;
                printf("Please enter the ID of the student to be deleted: ");
                scanf("%d", &id);
                head = delete_student_info(head, id);
                break;
            }
            case 6: {
                print_all_student_info(head);
                break;
            }
            case 7: {
                char filename[50];
                printf("Please enter the name of the file to save student information: ");
                scanf("%s", filename);
                save_student_info_to_file(head, filename);
                break;
            }
            case 8: {
                char filename[50];
                printf("Please enter the name of the file to load student information: ");
                scanf("%s", filename);
                head = load_student_info_from_file(head, filename);
                break;
            }
            case 9: {
                sort_student_info(head, compare_by_id);
                printf("Sort student information by ID successfully.\n");
                break;
            }
            case 10: {
                sort_student_info(head, compare_by_name);
                printf("Sort student information by name successfully.\n");
                break;
            }
            default:
                printf("Invalid choice.\n");
        }
    }
    return 0;
}

该程序使用单链表存储学生信息，具有创建、输入、查询、修改、删除、输出、保存到文件、从文件加载等功能，并且实现了按ID和姓名排序的功能。您可以根据需要对程序进行修改和扩展。