package day1;
import javax.swing.JOptionPane;
public class day1HomeWork {
public static String[] number = new String[20];
public static String[] name = new String[20];
public static double[] score = new double[20];
public static int num = 0;
public static void main(String[] args) {
// TODO Auto-generated method stub
JOptionPane.showMessageDialog(null,"欢迎光临");
boolean flag = login();
if (flag == false){
JOptionPane.showMessageDialog(null,"非法用户");
System.exit(-1);
}
while (true){
String input = JOptionPane.showInputDialog(null,"1、添加\n2、显示\n"
+ "3、删除\n4、查找\n5、修改\n6、排序\n7、退出");
char ch = input.toCharArray()[0];
switch (ch){
case '1':
addStudent();
break;
case '2':
showStudent();
break;
case '3':
deleteStudent();
break;
case '4':
queryStudent();
break;
case '5':
updateStudent();
break;
case '6':
sortStudent();
break;
case '7':
JOptionPane.showMessageDialog(null,"谢谢使用");
System.exit(-1);
break;
default:
JOptionPane.showMessageDialog(null, "输入有误，请重新输入（1-7）");
}
}
}
public static boolean login(){//登录
for (int i=0; i<3; i++){
String userName = JOptionPane.showInputDialog(null,"请输入用户名");
int pwd = Integer.parseInt(JOptionPane.showInputDialog(null,"请输入密码"));
if (userName.equals("lwz") && pwd == 1992){
return true;
}
else{
JOptionPane.showMessageDialog(null,"用户名或密码错误");
}
}
return false;
}
public static void addStudent(){//添加学生信息
String codeStr = JOptionPane.showInputDialog(null,"请输入学号");
String nameStr = JOptionPane.showInputDialog(null,"请输入姓名");
double grade = Double.parseDouble(JOptionPane.showInputDialog(null,"请输入成绩"));
number[num] = codeStr;
name[num] = nameStr;
score[num] = grade;
num++;
}
public static void showStudent(){//显示学生信息
String str = "学号 姓名 成绩\n";
for (int i=0; i
// if (number[i] == null)
// continue;
str += number[i]+" "+name[i]+" "
+score[i]+"\n";
}
JOptionPane.showMessageDialog(null,str);
}
public static void deleteStudent(){//删除学生信息
String input = JOptionPane.showInputDialog(null, "请输入姓名");
int index = -1;
for (int i=0; i
if (name[i].equals(input)){
index = i;
}
}
if (index == -1){
JOptionPane.showMessageDialog(null, "没有找到该学生");
return;
}
for (int i=index; i
number[i] = number[i+1];
name[i] = name[i+1];
score[i] = score[i+1];
}
num--;
showStudent();
}
public static void queryStudent(){//查找
int index = -1;
String str = "学号 姓名 成绩\n";
String input = JOptionPane.showInputDialog(null,"请输入姓名");
for (int i=0; i
if (name[i].equals(input)){
index = i;
str += number[i]+" "+name[i]+" "+score[i]+"\n";
}
}
if (index == -1){
JOptionPane.showMessageDialog(null,"没有找到该学生");
}
else{
JOptionPane.showMessageDialog(null,str);
}
}
public static void updateStudent(){//修改
int index = -1;
String input = JOptionPane.showInputDialog(null,"请输入姓名");
for (int i=0; i
if (name[i].equals(input)){
index = i;
String strNum = JOptionPane.showInputDialog(null,"请输入学号");
number[i] = strNum;
String strName = JOptionPane.showInputDialog(null,"请输入姓名");
name[i] = strName;
double s = Double.parseDouble(JOptionPane.showInputDialog(null,"请输入成绩"));
score[i] = s;
}
}
if (index == -1){
JOptionPane.showMessageDialog(null, "没有找到该学生");
return;
}
String str = "学号 姓名 成绩\n";
for (int i=0; i
str += number[i]+" "+name[i]+" "+score[i]+"\n";
}
JOptionPane.showMessageDialog(null, str);
}
public static void sortStudent(){//排序
for (int i=0; i
for (int j=i+1; j
if (score[i] < score[j]){
String s = number[i];
number[i] = number[j];
number[j] = s;
String n = name[i];
name[i] = name[j];
name[j] = n;
double temp = score[i];
score[i] = score[j];
score[j] = temp;
}
}
}
showStudent();
}
}
