C# 验证IP是否正确简易方法 源代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace 验证IP合法性
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {

            try
            {
                string[] format = new string[4];
                string s = ".";
                format = textBox1.Text.Split(s.ToCharArray(), 4);
                for (int i = 0; i < 4; i++)
                {

                    if (Convert.ToInt32(format[i]) >= 255)
                    {

                        MessageBox.Show("IP地址不合法");
                        if (Convert.ToInt32(format[i]) <= 255)
                        {
                            MessageBox.Show("IP地址正确");
                        }

                    }
                    MessageBox.Show("IP地址正确");
                }
            }
            catch
            {
                MessageBox.Show("IP地址不合法");

            }

        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }
    }
}