diff --git "a/01 \350\213\217\346\270\205\345\215\216/20221220 \345\255\246\347\224\237\347\256\241\347\220\206\347\263\273\347\273\237.md" "b/01 \350\213\217\346\270\205\345\215\216/20221220 \345\255\246\347\224\237\347\256\241\347\220\206\347\263\273\347\273\237.md" index eced5b1c873e746a6896a60b8eed1e35ab5480b0..95290e44f690177acc637ccedff21dbd17a96765 100644 --- "a/01 \350\213\217\346\270\205\345\215\216/20221220 \345\255\246\347\224\237\347\256\241\347\220\206\347\263\273\347\273\237.md" +++ "b/01 \350\213\217\346\270\205\345\215\216/20221220 \345\255\246\347\224\237\347\256\241\347\220\206\347\263\273\347\273\237.md" @@ -36,104 +36,159 @@ public class a1 { import java.util.Scanner; public class a2 { + static Scanner sc = new Scanner(System.in); + static String[] stu = new String[40]; public static void main(String[] args) { - System.out.println("==================================" + - "\n-- 欢迎使用3班学生管理系统 \t\t--" + - "\n--\t 1.浏览所有学生信息 \t\t--" + - "\n--\t 2.添加学生信息 \t\t\t--" + - "\n--\t 3.修改学生信息 \t\t\t--" + - "\n--\t 4.删除学生信息 \t\t\t--" + - "\n--\t 5.查询学生信息 \t\t\t--" + - "\n--\t 6.退出管理系统 \t\t\t--" + - "\n=================================="); - String[] student = new String[40]; - Scanner sc = new Scanner(System.in); - a: - for (; ; ) { - System.out.println("请输入对应的数字选择你需要的功能："); - int num = sc.nextInt(); - switch (num) { - case 1: - browse(student); - break; - case 2: - System.out.println("请输入要添加的学生姓名："); - String addname=sc.next(); - add(student,addname); - break; - case 3: - System.out.println("请输入要修改的学生姓名："); - String changename1= sc.next(); - if (n(student,changename1)==0){ - System.out.println("请输入新姓名："); - String changename2= sc.next(); - change(student,changename1,changename2); - }else - System.out.println("不存在该学生，无法修改！"); - break; - case 4: - break; - case 5: - break; - case 6: - break; - default: - System.out.println("选项错误"); - } - } - } - //1.浏览 - public static void browse(String[] student) { - System.out.println("你正在浏览三班学生名单："); - for (int i = 0; i < student.length; i++) { - if (student[i] == null) { - continue; + stu[0] = "张三"; + stu[1] = "李四"; + + aa: while (true){ + Welcome(); + int a = choice(sc.nextInt()); + if (a==1){ + break ;//中止while } - System.out.print(student[i]+"\t"); } + } - //2.添加 - public static void add(String [] student,String name){ - for (int i=0;i< student.length;i++){ - if (student[i]!=null){ - if (student[i].equals(name)){ - System.out.println("该学生已存在。"); - break; - } - }else { - student[i]=name; - System.out.println("添加成功！"); + + public static void Welcome() { + System.out.println( + "\n============================" + + "\n- 欢迎使用3班学生管理系统 --" + + "\n- 1.浏览所有学生信息 -" + + "\n- 2.添加学生信息 -" + + "\n- 3.修改学生信息 -" + + "\n- 4.删除学生信息 -" + + "\n- 5.查询学生信息 -" + + "\n- 6.退出管理系统 -" + + "\n =========================" + + "\n请输入对应的数字选择你需要的功能："); + } + //菜单选择 + public static int choice(int num){ + int a =0; + switch (num) { + case 1: + //浏览 + Allstudent(); break; - } + case 2: + //添加 + addstudent(); + break; + case 3: + //修改 + editStudent(); + break; + case 4: + //删除 + deleteStudent(); + break; + case 5: + //查询 + searchStudent(); + break; + case 6: + //结束 + System.out.println("你选择了退出系统"); + default: + System.out.println("你输入的选项错误"); + a=1; } + return a; } -// 3.修改 - public static void change(String[] student,String name1,String name2){ - for (int i=0;i< student.length;i++){ - if (name1.equals(student[i])){ - student[i]=name2; - System.out.println("修改成功！"); - break; - } + //4.删除学生信息 + private static void deleteStudent() { + System.out.println("请问你要删除哪个学生"); + String name= sc.next(); + int index =search(name); + if (index==-1){ + System.out.println("对不起，没有该学生，无法删除"); + }else { + stu[index]=null; + System.out.println("删除成功"); + } + } + //5.查找 + public static void searchStudent(){ + System.out.println("请输入要查找的学生姓名"); + String name =sc.next(); + int index =search(name); + if (index==-1){ + System.out.println("未找到该生。"); + }else { + System.out.println("恭喜，找到了，Ta在第"+(index+1)+"个"); + } + } + //3.修改 + private static void editStudent(){ + System.out.println("请问你要修改那个学生"); + String name =sc.next(); + int index =search(name); + if (index==-1){ + System.out.println("未找到该生，无法修改"); + }else { + System.out.println("请问你要把【"+name+"】修改为："); + String newNmae = sc.next(); + stu[index]= newNmae; + System.out.println("修改成功！"); } } - public static int n(String[] student,String name){ - boolean m=false; - for (int i=0;i< student.length;i++){ - if (student[i]!=null){ - if (student[i].equals(name)) - m=true; + //1.浏览 + public static void Allstudent() { + System.out.println("3班学生如下："); + int count =0; + for (String name : stu) { + if (name==null){ + count++; + continue; } + System.out.print(name + "\t"); + } + if (count== stu.length){ + System.out.println("目前还没有学生信息"); } - if (m){ - return 0; + } + // 2.添加 + public static void addstudent() { + System.out.println("请输入你要添加的学生"); + String name = sc.next(); + int index = search( name); + if (index != -1) { + System.out.println("该学生已经存在，请不要重复添加"); + } else { + int nullIndex = search(null); + stu[nullIndex] = name; + System.out.println("添加成功"); + Allstudent(); + + } + } + + public static int search( String str) { + int index = -1; + if (str == null) { + for (int i = 0; i < stu.length; i++) { + if (stu[i]==null){ + index = i; + break; + } + } }else { - return 1; + for (int i = 0; i < stu.length; i++) { + if (str.equals(stu[i])) { + index=i; + return index; + } + } } - } + return index; + } + } ```