C# 簡易的 NSLookUp

JDP

using System;<br /> using System.Net;<br /> namespace nslookup<br /> {<br /> /// <summary><br /> /// <br /> /// <title>nslookup</title><br /> /// <description><br /> /// *nix simple nslookup clone for the Win32 platform (Console Application)<br /> /// Does A DNS lookup by Host Name or IP. Host Name lookups can return<br /> /// multiple IP Ranges.<br /> /// </description><br /> /// <author>Doug Bell</author><br /> /// <version>1.0</version><br /> /// <date>March 23 2002</date><br /> /// <br /> /// </summary><br /> class NSLookup<br /> {<br /> /// <summary><br /> /// <br /> /// <description>Application entry point.</description><br /> /// <param name="args">Host Address, IP Address or -help command line <br /> options</param><br /> /// <return>int Return code 0 for success -1 for failure or error</return><br /> /// <br /> /// </summary><br /> [STAThread]<br /> static int Main(string[] args)<br /> {<br /> //Make sure we were passed something, otherwise return help.<br /> if (args.Length < 1 || args[0].Equals("-help"))<br /> {<br /> Console.WriteLine("Usage is: nslookup [Host Name] | [Host IP] | -help");<br /> Console.WriteLine("nslookup foo.bar.com (Returns IP Address for Host Name)");<br /> Console.WriteLine("nslookup 123.123.123.123 (Returns Host Name for Address)");<br /> Console.WriteLine("nslookup -help (Returns this Help Message)");<br /> return -1;<br /> }<br /> else<br /> {<br /> //We have something, try to look it up....<br /> try<br /> {<br /> //The IP or Host Entry to lookup<br /> IPHostEntry ipEntry;<br /> //The IP Address Array. Holds an array of resolved Host Names.<br /> IPAddress [] ipAddr;<br /> //Value of alpha characters<br /> char[] alpha = "aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ-".ToCharArray();<br /> //If alpha characters exist we know we are doing a forward lookup<br /> if (args[0].IndexOfAny(alpha) != -1)<br /> {<br /> ipEntry = Dns.GetHostByName (args[0]);<br /> ipAddr = ipEntry.AddressList;<br /> Console.WriteLine("\nHost Name : " + args[0]);<br /> int i = 0;<br /> int len = ipAddr.Length;<br /> for (i = 0; i < len; i++)<br /> {<br /> Console.WriteLine ("Address {0} : {1} ", i, ipAddr<i>.ToString ());<br /> }<br /> return 0;<br /> }<br /> //If no alpha characters exist we do a reverse lookup<br /> else <br /> {<br /> ipEntry = Dns.Resolve(args[0]);<br /> Console.WriteLine("Address : " + args[0]);<br /> Console.WriteLine("Host Name : " + ipEntry.HostName);<br /> return 0;<br /> }<br /> }<br /> catch(System.Net.Sockets.SocketException se)<br /> {<br /> // The system had problems resolving the address passed<br /> Console.WriteLine(se.Message.ToString());<br /> return -1;<br /> }<br /> catch(System.FormatException fe)<br /> {<br /> // Non unicode chars were probably passed <br /> Console.WriteLine(fe.Message.ToString());<br /> return -1;<br /> }<br /> }<br /> }//End Main(string[])<br /> }//End NSLookup Class<br /> }//End nslookup namespace

Reference: http://www.c-sharpcorner.com/Upl ... /NSLookUpDB001.aspx