c语言学生信息管理系统代码_c语言的应用以及未来发展

c语言学生信息管理系统代码_c语言的应用以及未来发展 问题描述：在文件studd.txt中存放学生信息，学生信息包含学号、姓名和成绩。

要求采用菜单形式实现学生记录的创建、添加、查找（按学号进行）、修改（按学号进行）和删除（按学号进行）、显示所有信息等功能。

用户可以循环 *** 作直到选择退出为止。

分析：本题是对文件的综合应用，采用菜单形式可以方便地实现程序模块的设计方法，这样可以使程序显得简洁明了。

设计时可以逐个完成各模块功能，并调试好每个模块，然后再整合各模块。

参考代码：#include<stdio.h>#include<stdlib.h>#include<string.h>#include<conio.h>struct student{ char no[10];char name[20];int score;};char filename[100]=”studd.txt”; /*设置文件名*/FILE *fp;void create(); /*创建函数声明*/void append(); /*添加函数声明*/void search(); /*查找函数声明*/void del(); /*删除函数声明*/void modify(); /*修改函数声明*/void output(); /*显示函数声明*/int main(void){int num;while(1){printf(” ***学生成绩系统***\n\n”);printf(” 1.创建记录 \n”);printf(” 2.添加记录 \n”);printf(” 3.查找记录 \n”);printf(” 4.修改记录 \n”);printf(” 5.删除记录 \n”);printf(” 6.显示记录 \n”);printf(” 0.退出系统 \n”);printf(“\n 选择序号0-6：” );scanf(“%d”,&num);if(num>=0&&num<=6){switch(num){ case 1:create();break;case 2:append();break;case 3:search();break;case 4:modify();break;case 5:del();break;case 6:output();break;case 0:exit(1);}printf(“\n\n *** 作完毕，请再次选择！\n”);}elseprintf(“\n\n选择错误，请再次选择！\n”);}getch();return 0;}/*创建记录*/void create(){struct student stu;if((fp=fopen(filename,”w”))==NULL){printf(“Cannot Open File!\n”);exit(0);}fprintf(fp,”%-10s%-20s%-50s\n”,”学号”,”姓名”,”成绩”);printf(“\n请输入学号、姓名及成绩(以0结束)\n”);scanf(“%s”,stu.no);while(strcmp(stu.no,”0″)){scanf(“%s %d”,stu.name,&stu.score);fprintf(fp,”%-10s%-20s%-50d\n”,stu.no,stu.name,stu.score);scanf(“%s”,stu.no);}fclose(fp);}/*添加记录*/void append(){struct student stu;if((fp=fopen(filename,”a”))==NULL){printf(“\nCannot Open File!”);exit(0);}printf(“\n请输入要添加的学号、姓名及成绩\n”);scanf(“%s%s%d”,stu.no,stu.name,&stu.score);fprintf(fp,”%-10s%-20s%-50d\n”,stu.no,stu.name,stu.score);fclose(fp);}/*查找记录*/void search(){int k=0;char nokey[10];struct student stu;printf(“\n请输入学号：”);scanf(“%s”,nokey);if((fp=fopen(filename,”r”))==NULL){printf(“\nCannot Open File!”);exit(0);}fseek(fp,1L*sizeof(struct student),0);while(!feof(fp)){fscanf(fp,”%s%s%d”,stu.no,stu.name,&stu.score);if(strcmp(nokey,stu.no)==0){printf(“\n\n已查找到，该记录为：\n\n”);printf(“%-10s%-20s%-50s”,”学号”,”姓名”,”成绩”);printf(“%-10s%-20s%-50d”,stu.no,stu.name,stu.score);k=1;}}if(!k)printf(“\n文件中无此人的记录。

”);fclose(fp);}/*修改记录*/void modify(){int k=0;long position;char nokey[10];struct student stu;printf(“\n请输入学号：”);scanf(“%s”,nokey);if((fp=fopen(filename,”r+”))==NULL){printf(“\nCannot Open File!”);exit(0);}fseek(fp,1L*sizeof(struct student),0);while(!feof(fp)){fscanf(fp,”%s%s%d”,stu.no,stu.name,&stu.score);if(strcmp(nokey,stu.no)==0){ position=ftell(fp);k=1;break;}}if(k){printf(“\n\n已查找到，该记录为：\n\n”);printf(“%-10s%-20s%-50s”,”学号”,”姓名”,”成绩”);printf(“%-10s%-20s%-50d”,stu.no,stu.name,stu.score);printf(“\n请输入新的学号、姓名及成绩：”);scanf(“%s%s%d”,stu.no,stu.name,&stu.score);fseek(fp,position-1L*sizeof(struct student),SEEK_SET);fprintf(fp,”\n%-10s%-20s%-50d”,stu.no,stu.name,stu.score);}elseprintf(“\n\n文件中无此人的记录。

”);fclose(fp);}/*删除记录*/void del(){int m,k=0;long position;char nokey[10];struct student stu;printf(“\n请输入学号：”);scanf(“%s”,nokey);if((fp=fopen(filename,”r+”))==NULL){printf(“\nCannot Open File!”);exit(0);}fseek(fp,1L*sizeof(struct student),0);while(!feof(fp)){fscanf(fp,”%s%s%d”,stu.no,stu.name,&stu.score);if(strcmp(nokey,stu.no)==0){ position=ftell(fp);k=1;break;}}if(k){printf(“\n\n已查找到，该记录为：\n\n”);printf(“%-10s%-20s%-50s”,”学号”,”姓名”,”成绩”);printf(“%-10s%-20s%-50d”,stu.no,stu.name,stu.score);printf(“\n确实要删除记录，请按1；不删除记录，请按0：”);scanf(“%d”,&m);if(m){fseek(fp,position-1L*sizeof(struct student),SEEK_SET);fprintf(fp,”%-10s%-20s%-50s”,””,””,””);}}elseprintf(“\n\n文件中无此人的记录。

”);fclose(fp);}/*显示记录*/void output(){struct student stu;if((fp=fopen(filename,”r”))==NULL){printf(“\nCannot Open File!”);exit(0);}printf(“\n\n文件内容为：\n”);fseek(fp,1L*sizeof(struct student),0);while(!feof(fp)){fscanf(fp,”%s%s%d\n”,stu.no,stu.name,&stu.score);printf(“%-10s%-20s%-50d”,stu.no,stu.name,stu.score);}fclose(fp);}