一.java数组增删改查实例1方法2

package com.hp.Test1006; import java.util.ArrayList; import java.util.Arrays; import java.util.List; import java.util.Scanner; public class Test { private static String[] str; public static void main(String[] args) { //创建string数组设置固定长度 // str = new String[]{"李磊","李雷","李蕾","李垒","李镭","李华","李花","利华"}; str = new String[10]; //传值 str[0] = "李磊"; str[1] = "李雷"; str[2] = "李蕾"; str[3] = "李垒"; str[4] = "李镭"; str[5] = "李华"; str[6] = "李花"; str[7] = "利华"; System.out.println("班级学生姓名："); for (int i = 0; i <str.length; i++) { System.out.print((i+1)+"."+str[i] + " "); } while (true) { System.out.println("欢迎来带学生管理系统"); System.out.println("\n==请选择操作序号==\n1.添加\n2.删除\n3.修改\n4.查询\n0.退出"); Scanner sc = new Scanner(System.in); String s = sc.nextLine(); if (s.equals("1")){ System.out.println("请输入要添加的内容:"); String name = sc.nextLine(); listAdd(str,name); System.out.println("以下是修改后的学生名单"); listShowAll(str); } if (s.equals("2")){ System.out.println("请输入要删除的id:"); int i = new Integer(sc.nextLine()); listDel(str,i-1); System.out.println("以下是修改后的学生名单"); listShowAll(str); } if (s.equals("3")){ System.out.println("请输入要修改的id:"); int i = new Integer(sc.nextLine()); System.out.println("请输入要修改的内容:"); String name = sc.nextLine(); listUpdate(str,i-1,name); System.out.println("以下是修改后的学生名单"); listShowAll(str); } if (s.equals("4")){ System.out.println("请输入要查询的id:"); int i = new Integer(sc.nextLine()); listQueryByIndex(str,i-1); } if (s.equals("0")){ System.out.println("再见"); break; } } } //增加 private static void listAdd(String[] str,String name){ str[str.length-2]=name; } //通过索引删除 private static void listDel(String[] str,int i){ // //将数组转为list // List<String> list1= Arrays.asList(str); // //调用list方法删除 // list1.remove(i); // //再转为数组 // list1.toArray(str); // //创建一个list集合 // List<String> list = new ArrayList<String>(); // //for循环遍历把值添加到list中 // for (int j = 0; j <str.length; j++){ // list.add(str[j]); // } // //通过索引删除 // list.remove(i); // System.out.println(list.toString()); // //转为string数组覆盖 // String[] strs = list.toArray(new String[list.size()]); // for (int j = 0; j <strs.length; j++) { // System.out.print(strs[j] + " "); // } //for循环 从删除的当前索引+1把数据进行替代 for (int j = i; j < str.length-1; j++) { str[j] = str[j + 1]; } } //通过索引修改 private static void listUpdate(String[] str,int i ,String name){ str[i]=name; } //全查询 private static void listShowAll(String[] str){ for (int i = 0; i < str.length; i++) { System.out.print(str[i] + " "); } } //根据索引查询 private static void listQueryByIndex(String[] str,int i){ System.out.println(str[i]); } }