(转)C#判断IP地址是否合法正则表达式 .
C#判断IP地址是否合法函数-使用正则表达式
var reg=/(\d{3})\.(\d{3})\.(\d{1,3})\.(\d{3})/ (常用方法)
//------方法一
public bool IsCorrenctIP(string ip)
{
string pattrn=@"(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])";
if(System.Text.RegularExpressions.Regex.IsMatch(ip,pattrn))
{
return true;
}
else
{
return false;
}
}
//------------方法二
public bool IsValidIP(string ip)
{
if (System.Text.RegularExpressions.Regex.IsMatch(ip,"[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}"))
{
string[] ips = ip.Split(\'.\');
if (ips.Length == 4 || ips.Length == 6)
{
if(System.Int32.Parse(ips[0]) < 256 && System.Int32.Parse(ips[1]) < 256 & System.Int32.Parse(ips[2]) < 256 & System.Int32.Parse(ips[3]) < 256)
return true;
else
return false;
}
else
return false;
}
else
return false;
}
//-----------------------方法三------------------------
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace CheckIP
{
publicpartialclass Form1 : Form
{
publicbool IsIP(string ip)
{
bool b =true;
string[] lines =newstring[4];
string s =".";
lines = ip.Split(s.ToCharArray(), 4);//分隔字符串
for (int i =0; i <4; i++)
{
if (Convert.ToInt32(lines[i]) >=255|| Convert.ToInt32(lines[i]) <0)
{
b =false;
return b;
}
}
return b;
}
publicbool isNu(string a)
{
}
public Form1()
{
InitializeComponent();
}
privatevoid btn_Check_Click(object sender, EventArgs e)
{
string x;
x = txt_IP.Text;
if (IsIP(x))
MessageBox.Show("你输入的是合法IP！");
else
MessageBox.Show("不是合法IP");
}
}
}
//-----------------------------------------------------------
Regex r = new Regex(@"^(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$");
string s = "192.168.1.1";
if (r.IsMatch(s))
{
}
//---------------------------------------------------------------------
|
try...
|