Creating domain Name query system with ASP

Query System | Domain Name Query

First, the principle:

The principle is very simple, domain name query is based on RFC 954 provided by the WHOIS protocol. In the implementation process, we access the NIC site's whois database server through our own Web server, query the WHOIS database for what we need, and then synthesize the page back to the client via ASP group.

At the same time, we use XMLHTTP protocol to achieve the client page without refreshing effect and to the server to retrieve WHOIS data requirements.

The specific process is: the client through XMLHTTP proposed domain name Query request-->web Server in the ASP listening page to accept the request, use XMLHTTP to send Retrieval command to the WHOIS server-->whois database to perform query operations, Return results to our own Web server (HTML form) after the-->web server receives the content, the results are delivered to the client-> the client browser uses VBScript to filter out the unwanted portions of the HTML, picking out the WHOIS data to display.

Second, ASP XMLHTTP programming Brief:

1. Client HTML page:

<script language= "VBScript" > Sub Submit1_onmouseup ' is triggered when clicking the ' Query ' button; Dim Objxml, objxsl, Objfso,strfile, strFileName, Strxsl,strurl,theform Set theform = Document.wordfind window.status= "Retrieving Data ..." Strurl= "Dns.asp" Set Objxml = CreateObject ("Microsoft.XMLHTTP") ' creates the XMLHTTP component of MS; Stra = "submit=submit&fqdn=" &theform.words.value Objxml.open "POST", Strurl,false ' using post submission method; Objxml.setrequestheader "Content-length", Len (stra) Objxml.setrequestheader "Content-type", "application/x-www-form-urlencoded" Objxml.send stra ' Send message Xmlget = Objxml.responsetext ' Wait a moment, get the result of the server-side return; If InStr (1,xmlget, "this are not a valid. com. net. org. info or. biz domain Name", 1) <1 and Len (Trim (xmlget)) >100 Then If InStr (1,xmlget, "This domain is available", 1) <1 Then If InStr (1,xmlget, "Registrant:", 1) Then StrFind1 =instr (1,xmlget, "Registrant:", 1) Else StrFind1 = InStr (1,xmlget, "<pre> <font face=" "Verdana, Arial", 1) +65

strfind2 = InStr (1,xmlget, " ", 1) Strfind4=strfind2-strfind1 SHTML = Mid (Xmlget,strfind1,strfind4) theform.comments.value= "Query results:" +CHR (13) + Chr (a) +shtml window.status= Query result: The domain name is already occupied else theform.comments.value= "Congratulations, this domain is available!" " window.status=" Query results: The domain name is still available! " End If Else theform.comments.value=" is not a valid international top-level domain name! Please enter an international domain name that ends with (. com. net. org. info or.), such as sun.com " window.status=", an invalid international top-level domain name! Please enter an international domain name that ends with (. com. net. org. info or.), such as cctv.com " End If Set objxml = Nothing End Sub p> XMLHTTP Domain name Query Chapter Please enter a domain name: form>

2, server-side ASP program:

<%dim Xmlget,objxml, objxsl, Objfso,strfile, strFileName, Strxsl,strurl Xmlget= "" If Len (Trim (Request.Form ("FQDN))") > 1 Then Strurl= "Http://www.domainbank.net/whoisresults_gen.cfm?show=1" ' The address of the WHOIS server Set Objxml = CreateObject ("Microsoft.XMLHTTP") ' creates the XMLHTTP component of MS Stra = "submit=submit&fqdn=" &trim (Request.Form ("FQDN") Objxml.open "POST", Strurl,false Objxml.setrequestheader "Content-length", Len (stra) Objxml.setrequestheader "Content-type", "application/x-www-form-urlencoded" Objxml.send stra ' send information to whois database server; Xmlget = Objxml.responsetext ' Get the information returned by the domain name server Set Objxml = Nothing End If Response.Write Xmlget ' return results to client %>

In the above process, we can find that the ASP program in our own Web server only acts as an intermediary, in practical applications, it can also omit this middle layer, using VBScript to send and receive data directly to the WHOIS database through XMLHTTP. However, this may be because the "access to data resources through (other) domain" in IE is disabled (the default) caused by insufficient permissions to cause the failure to execute, so the method of eliminating ASP middle tier is not very common.

This program runs on the IIS5.0 and IE6.0 based on the Windows2000 platform. The actual use of the process, you can copy the above code to their own web page, after a simple page editing, you can add in their own pages in the page without refreshing the domain name query function, at first look, it is really a bit like a professional domain name registrar services provided by the website.