5.list集合添加姓名{张三,李四,王五,二丫,钱六,孙七},将二丫替换为王小丫, 写入到"D:\stuinfo.txt"

Posted 2021-02-16 zhilili

package cn.it.text;

import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;

/*
 * 5.list集合添加姓名{张三,李四,王五,二丫,钱六,孙七},将二丫替换为王小丫,
 * 写入到"D:\stuinfo.txt"
 */
public class Test5 {
    public static ArrayList<String> list = new ArrayList<String>();

    public static void main(String[] args) throws IOException {
        chushihua();
        printList();

    }

    public static void chushihua() {
        // 初始化集合，添加元素
        list.add("张三");
        list.add("李四");
        list.add("王五");
        list.add("二丫");
        list.add("钱六");
        list.add("孙七");

        // 输出集合
        System.out.println("集合原先的元素为：");
        for (String name : list) {
            System.out.print(name + " ");
        }
        System.out.println();

        // 替换集合中的元素
        for (String name : list) {
            if (name.equals("二丫")) {
                int index = list.indexOf(name);
                list.set(index, "王小丫");
            } else {
                continue;
            }
        }
        // 输出替换后的集合
        System.out.println("替换后的集合为：");
        for (String name : list) {
            System.out.print(name + " ");
        }
    }

    // 将集合中的元素写入文件中
    public static void printList() throws IOException {
        // 创建一个输出流对象
        FileWriter out = new FileWriter("D:\stuinfo.txt");
        String str = list.toString();
        out.write(str);
        out.close();

    }

}