學(xué)生成績管理系統(tǒng)的C語言程序設(shè)計(jì)

1、#include "stdio.h"/*定義學(xué)生結(jié)構(gòu)體*/struct Student char ID20; /* 學(xué)號(hào) */char Name20;/* 姓名 */float Mark1; /* 數(shù)學(xué)成績*/float Mark2; /* 程序設(shè)計(jì)成績*/float Mark3; /* 總分成績*/float Average; /* 平均分 */;/*聲明學(xué)生數(shù)組及學(xué)生數(shù)量*/struct Student students1000;int num=0;/*求平均值*/float Avg(struct Student stu)return (stu.Mark1+stu.Ma

2、rk2+stu.Mark3)/3;/*通過學(xué)號(hào)返回?cái)?shù)組下標(biāo)*/int Student_SearchByIndex(char id)int i;for (i=0;i<num;i+)if (strcmp(studentsi.ID,id)=0)return i;return -1;/*通過姓名返回?cái)?shù)組下標(biāo)*/int Student_SearchByName(char name)int i;for (i=0;i<num;i+)if (strcmp(studentsi.Name,name)=0)return i;return -1;/*顯示單條學(xué)生記錄*/void Student_Displ

3、aySingle(int index)printf("%10s%10s%8s%8s%8s%10sn"," 學(xué)號(hào) ","姓名","成績","成績","成績","平均成績");printf("n");printf("%10s%10s%8.2f%8.2f%8.2f%10.2fn",studentsindex.ID,studentsindex.Name,studentsindex.Mark1,studentsindex.Ma

4、rk2,studentsindex.Mark3,studentsindex.Aver age);/*增加學(xué)生記錄*/void Student_Insert()while(1)printf(" 請(qǐng)輸入學(xué)號(hào):");scanf("%s",&studentsnum.ID);getchar();printf(" 請(qǐng)輸入姓名:");scanf("%s",&studentsnum.Name);getchar();printf(" 請(qǐng)輸入數(shù)學(xué)成績:");scanf("%f",

5、&studentsnum.Mark1);getchar();printf(" 請(qǐng)輸入設(shè)計(jì)報(bào)告成績:");scanf("%f",&studentsnum.Mark2);getchar();printf(" 請(qǐng)輸入總分成績:");scanf("%f",&studentsnum.Mark3);getchar();studentsnum.Average=Avg(studentsnum);num+;printf(" 是否繼續(xù)?(y/n)");if (getchar()='n

6、')break;/*修改學(xué)生信息*/void Student_Modify()float mark1,mark2,mark3;while(1)char id20;int index;printf(" 請(qǐng)輸入要修改的學(xué)生的學(xué)號(hào):");scanf("%s",&id);getchar();index=Student_SearchByIndex(id);if (index=-1)printf(" 學(xué)生不存在!n");elseprintf(" 你要修改的學(xué)生信息為:n");Student_DisplaySin

7、gle(index);printf("- 請(qǐng)輸入新值-n");printf(" 請(qǐng)輸入學(xué)號(hào):");scanf("%s",&studentsindex.ID);getchar();printf(" 請(qǐng)輸入姓名:");scanf("%s",&studentsindex.Name);getchar();printf(" 請(qǐng)輸入數(shù)學(xué)成績:");scanf("%f",&studentsindex.Mark1);getchar();printf

8、(" 請(qǐng)輸入設(shè)計(jì)報(bào)告成績:");scanf("%f",&studentsindex.Mark2);getchar();printf(" 請(qǐng)輸入總分成績:");scanf("%f",&studentsindex.Mark3);getchar();studentsindex.Average=Avg(studentsindex);printf(" 是否繼續(xù)?(y/n)");if (getchar()='n')break;/*刪除學(xué)生信息*/void Student_De

9、lete()int i;while(1) char id20;int index;printf(" 請(qǐng)輸入要?jiǎng)h除的學(xué)生的學(xué)號(hào):");scanf("%s",&id);getchar();index=Student_SearchByIndex(id);if (index=-1)printf(" 學(xué)生不存在!n");elseprintf(" 你要?jiǎng)h除的學(xué)生信息為:n");Student_DisplaySingle(index);printf(" 是否真的要?jiǎng)h除?(y/n)");if (getc

10、har()='y')for (i=index;i<num-1;i+)studentsi=studentsi+1;num-;getchar();printf(" 是否繼續(xù)?(y/n)");if (getchar()='n')break;/*按姓名查詢*/void Student_Select()while(1)char name20;int index;printf(" 請(qǐng)輸入要查詢的學(xué)生的姓名:");scanf("%s",&name);getchar();index=Student_Sea

11、rchByName(name);if (index=-1) printf(" 學(xué)生不存在!n");elseprintf(" 你要查詢的學(xué)生信息為:n");Student_DisplaySingle(index);printf(" 是否繼續(xù)?(y/n)");if (getchar()='n')break;/*按平均值排序*/void Student_SortByAverage()int i,j;struct Student tmp;for (i=0;i<num;i+)for (j=1;j<num-i;j+)i

12、f (studentsj-1.Average<studentsj.Average)tmp=studentsj-1;studentsj-1=studentsj;studentsj=tmp;/*顯示學(xué)生信息*/void Student_Display() int i;printf("%10s%10s%8s%8s%8s%10sn"," 學(xué)號(hào) ","姓名 ","成績 ","成績","成績","平均成績");printf("n");for

13、(i=0;i<num;i+)printf("%10s%10s%8.2f%8.2f%8.2f%10.2fn",studentsi.ID,studentsi.Name, studentsi.Mark1,studentsi.Mark2,studentsi.Mark3,studentsi.Average); /*將學(xué)生信息從文件讀出*/void IO_ReadInfo() FILE *fp;int i;if (fp=fopen("Database.txt","rb")=NULL)printf(" 不能打開文件!n")

14、;return;if (fread(&num,sizeof(int),1,fp)!=1)num=-1;elsefor(i=0;i<num;i+)fread(&studentsi,sizeof(struct Student),1,fp);fclose(fp);/*將學(xué)生信息寫入文件*/void IO_WriteInfo()FILE *fp;int i;if (fp=fopen("Database.txt","wb")=NULL)printf(" 不能打開文件!n");return;if (fwrite(&n

15、um,sizeof(int),1,fp)!=1)printf(" 寫入文件錯(cuò)誤!n");for (i=0;i<num;i+)if (fwrite(&studentsi,sizeof(struct Student),1,fp)!=1)printf（" 寫入文件錯(cuò)誤!n"）;fclose(fp);/*主程序*/main()int choice;IO_ReadInfo();while(1)/*主菜單*/n");printf("n 學(xué)生成績管理系統(tǒng)-printf("1.增加學(xué)生記錄n");printf("2.修改學(xué)生記錄n");printf("3.刪除學(xué)生記錄n");printf("4. 按姓名查詢學(xué)生記錄n");printf("5. 按平均成績排序n");printf("6. 退出 n");printf(" 請(qǐng)選擇 (1-6):");scanf("%d",