C#中List的Sort()、Find()、FindAll()、Exist()的使用方法
C#中List的Sort()、Find()、FindAll()、Exist()的使用方法
public class student
{
public int Number { get; set; }
public string Name { get; set; }
public bool Sex { get; set; }
public student(int _number, string _name, bool _sex)
{
Number = _number;
Name = _name;
Sex = _sex;
}
public override string ToString()
{
return string.Format("序号:{0},姓名:{1},性别:{2}",
Number.ToString(), Name, Sex ? "男" : "女");
}
}
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace ListSortTest
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
List<student> Students = new List<student>();
private void Form1_Load(object sender, EventArgs e)
{
Students.Add(new student(1, "张一", true));
Students.Add(new student(3, "张二", false));
Students.Add(new student(5, "张三", true));
Students.Add(new student(2, "张四", false));
Students.Add(new student(4, "张五", true));
Students.Add(new student(6, "张六", false));
}
//排序按钮
private void button1_Click(object sender, EventArgs e)
{
richTextBox1.Text += "**原始显示:\r\n";
showList(Students);
richTextBox1.Text += "\r\n**用序号排序从小到大显示:\r\n";
Students.Sort((x, y) => x.Number < y.Number ? -1 : 0);
showList(Students);
richTextBox1.Text += "\r\n**用序号排序从大到小显示:\r\n";
Students.Sort((x, y) => x.Number > y.Number ? -1 : 0);
showList(Students);
richTextBox1.Text += "\r\n**用姓名排序(升序)显示:\r\n";
Students.Sort((x, y) => x.Name.CompareTo(y.Name));
showList(Students);
richTextBox1.Text += "\r\n**用姓名排序(降序)显示:\r\n";
Students.Sort((x, y) => y.Name.CompareTo(x.Name));
showList(Students);
richTextBox1.Text += "\r\n**用性别排序(升序)显示:\r\n";
Students.Sort((x, y) => x.Sex.CompareTo(y.Sex));
showList(Students);
}
private void showList(List<student> _list)
{
for (int i = 0; i < _list.Count; i++)
{
richTextBox1.Text += _list[i].ToString() + "\r\n";
}
}
private void button2_Click(object sender, EventArgs e)
{
richTextBox1.Text += "\r\n**找出Name=\"张四\"的学生:\r\n";
richTextBox1.Text += Students.Find((student s) => s.Name == "张四").ToString();
richTextBox1.Text += "\r\n\r\n**找出第一个男学生:";
richTextBox1.Text += "(该方法只会找到第一个就停止)\r\n";
richTextBox1.Text += Students.Find((student s) => s.Sex == true).ToString();
richTextBox1.Text += "\r\n\r\n**找出所有女学生:\r\n";
showList(Students.FindAll((student s) => s.Sex == false));
richTextBox1.Text += "\r\n\r\n**判断“张四”学生是否存在:\r\n";
richTextBox1.Text += Students.Exists((student s) => s.Name == "张四" ? true : false).ToString();
}
}
}
