blocks|key|4072350|text|是的，这是可能的用途：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4072351|Uri.GetLeftPart(+UriPartial.Authority+)|code-block|syntax|javascript|4072352|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Yes, it is possible use: 

<pre><code>Uri.GetLeftPart( UriPartial.Authority )
</code></pre>

blocks|key|4072512|text|@Dewfy:缺点是您的方法返回"www.test.co.uk“的"uk”，但这里的域显然是"test.co.uk“。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4072513|@naivists:缺陷是您的方法为"www.beta.microsoft.com“返回"beta.microsoft.com”，但这里的域显然是"microsoft.com“。|4072514|我需要同样的东西，所以我写了一个类，你可以复制并粘贴到你的解决方案中。它使用TLD.http://pastebin.com/raw.php?i=VY3DCNhp的硬编码字符串数组|offset|length|4072515|Console.WriteLine(GetDomain.GetDomainFromUrl("http://www.beta.microsoft.com/path/page.htm"));|code-block|syntax|javascript|4072516|输出microsoft.com|style|CODE|4072517|和|4072518|Console.WriteLine(GetDomain.GetDomainFromUrl("http://www.beta.microsoft.co.uk/path/page.htm"));|4072519|输出microsoft.co.uk|4072520|entityMap|0|LINK|mutability|MUTABLE|url|http://pastebin.com/raw.php?i=VY3DCNhp^0|0|0|16|12|0|0|0|2|D|0|0|0|2|F|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|15|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|16|8|@]|9|@$F|17|G|18|1|19]]|A|$]]|$1|H|3|I|5|J|7|1A|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|1B|8|@$F|1C|G|1D|O|P]]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1E|8|@]|9|@]|A|$]]|$1|S|3|T|5|J|7|1F|8|@]|9|@]|A|$K|L]]|$1|U|3|V|5|6|7|1G|8|@$F|1H|G|1I|O|P]]|9|@]|A|$]]|$1|W|3|-4|5|6|7|1J|8|@]|9|@]|A|$]]]|X|$Y|$5|Z|10|11|A|$12|13]]]]

@Dewfy: flaw is that your method returns "uk" for "www.test.co.uk" but the domain here is clearly "test.co.uk".

@naivists: flaw is that your method returns "beta.microsoft.com" for "www.beta.microsoft.com" but the domain here is clearly "microsoft.com"

I needed the same, so I wrote a class that you can copy and paste into your solution. It uses a hard coded string array of tld's. <a href="http://pastebin.com/raw.php?i=VY3DCNhp" rel="noreferrer">http://pastebin.com/raw.php?i=VY3DCNhp</a>

<pre><code>Console.WriteLine(GetDomain.GetDomainFromUrl("http://www.beta.microsoft.com/path/page.htm"));
</code></pre>

outputs <code>microsoft.com</code>

and

<pre><code>Console.WriteLine(GetDomain.GetDomainFromUrl("http://www.beta.microsoft.co.uk/path/page.htm"));
</code></pre>

outputs <code>microsoft.co.uk</code>

blocks|key|5490582|text|不能保证google.com与www.google.com相同(在本例中，从技术上讲是相同的，但也可能与之不同)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5490583|也许你真正需要的是删除“顶级”域和"www“subodmain？然后只需使用split('.')，并在最后一部分之前的部分！|offset|length|style|CODE|5490584|entityMap^0|0|12|A|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

google.com is not guaranteed to be the same as www.google.com (well, for this example it technically is, but may be otherwise).

maybe what you need is actually remove the "top level" domain and the "www" subodmain? Then just <code>split('.')</code> and take the part before the last part!

blocks|key|4072740|text|我尝试了几乎所有的方法，但它们都没有达到预期的结果。所以这里是我从servermanfail中调整的方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4072741|tld文件可以在https://publicsuffix.org/list/上找到，我已经从https://publicsuffix.org/list/effective_tld_names.dat获取了这个文件，解析它并搜索tld，如果发布了新的tld，只需下载最新的文件即可。|offset|length|4072742|玩得开心。|4072743|using+System;
using+System.Collections.Generic;
using+System.IO;

namespace+SearchWebsite
{
internal+class+NetDomain
{
++++static+public+string+GetDomainFromUrl(string+Url)
++++{
++++++++return+GetDomainFromUrl(new+Uri(Url));
++++}

++++static+public+string+GetDomainFromUrl(string+Url,+bool+Strict)
++++{
++++++++return+GetDomainFromUrl(new+Uri(Url),+Strict);
++++}

++++static+public+string+GetDomainFromUrl(Uri+Url)
++++{
++++++++return+GetDomainFromUrl(Url,+false);
++++}

++++static+public+string+GetDomainFromUrl(Uri+Url,+bool+Strict)
++++{
++++++++initializeTLD();
++++++++if+(Url+==+null)+return+null;
++++++++var+dotBits+=+Url.Host.Split('.');
++++++++if+(dotBits.Length+==+1)+return+Url.Host;+//eg+http://localhost/blah.php+=+"localhost"
++++++++if+(dotBits.Length+==+2)+return+Url.Host;+//eg+http://blah.co/blah.php+=+"localhost"
++++++++string+bestMatch+=+"";
++++++++foreach+(var+tld+in+DOMAINS)
++++++++{
++++++++++++if+(Url.Host.EndsWith(tld,+StringComparison.InvariantCultureIgnoreCase))
++++++++++++{
++++++++++++++++if+(tld.Length+>+bestMatch.Length)+bestMatch+=+tld;
++++++++++++}
++++++++}
++++++++if+(string.IsNullOrEmpty(bestMatch))
++++++++++++return+Url.Host;+//eg+http://domain.com/blah+=+"domain.com"

++++++++//add+the+domain+name+onto+tld
++++++++string[]+bestBits+=+bestMatch.Split('.');
++++++++string[]+inputBits+=+Url.Host.Split('.');
++++++++int+getLastBits+=+bestBits.Length+%2B+1;
++++++++bestMatch+=+"";
++++++++for+(int+c+=+inputBits.Length+-+getLastBits;+c+<+inputBits.Length;+c%2B%2B)
++++++++{
++++++++++++if+(bestMatch.Length+>+0)+bestMatch+%2B=+".";
++++++++++++bestMatch+%2B=+inputBits[c];
++++++++}
++++++++return+bestMatch;
++++}


++++static+private+void+initializeTLD()
++++{
++++++++if+(DOMAINS.Count+>+0)+return;

++++++++string+line;
++++++++StreamReader+reader+=+File.OpenText("effective_tld_names.dat");
++++++++while+((line+=+reader.ReadLine())+!=+null)
++++++++{
++++++++++++if+(!string.IsNullOrEmpty(line)+&&+!line.StartsWith("//"))
++++++++++++{
++++++++++++++++DOMAINS.Add(line);
++++++++++++}
++++++++}
++++++++reader.Close();
++++}


++++//+This+file+was+taken+from+https://publicsuffix.org/list/effective_tld_names.dat

++++static+public+List<String>+DOMAINS+=+new+List<String>();
}|code-block|syntax|javascript|4072744|}|4072745|entityMap|0|LINK|mutability|MUTABLE|url|https://publicsuffix.org/list/|1|https://publicsuffix.org/list/effective_tld_names.dat^0|0|8|U|0|1A|1H|1|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Z|8|@]|9|@$D|10|E|11|1|12]|$D|13|E|14|1|15]]|A|$]]|$1|F|3|G|5|6|7|16|8|@]|9|@]|A|$]]|$1|H|3|I|5|J|7|17|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|18|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|19|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]|W|$5|R|S|T|A|$U|X]]]]

I tried pretty much every approach but all of them fell short of the desired result. 
So here is my approach adjusted from servermanfail.

The tld file is available on <a href="https://publicsuffix.org/list/" rel="noreferrer">https://publicsuffix.org/list/</a>
I have taken the file from <a href="https://publicsuffix.org/list/effective_tld_names.dat" rel="noreferrer">https://publicsuffix.org/list/effective_tld_names.dat</a> parse it and search for the tld's. If new tld's are published just download the latest file.

have fun.

<pre><code>using System;
using System.Collections.Generic;
using System.IO;

namespace SearchWebsite
{
internal class NetDomain
{
 static public string GetDomainFromUrl(string Url)
 {
 return GetDomainFromUrl(new Uri(Url));
 }

 static public string GetDomainFromUrl(string Url, bool Strict)
 {
 return GetDomainFromUrl(new Uri(Url), Strict);
 }

 static public string GetDomainFromUrl(Uri Url)
 {
 return GetDomainFromUrl(Url, false);
 }

 static public string GetDomainFromUrl(Uri Url, bool Strict)
 {
 initializeTLD();
 if (Url == null) return null;
 var dotBits = Url.Host.Split('.');
 if (dotBits.Length == 1) return Url.Host; //eg http://localhost/blah.php = "localhost"
 if (dotBits.Length == 2) return Url.Host; //eg http://blah.co/blah.php = "localhost"
 string bestMatch = "";
 foreach (var tld in DOMAINS)
 {
 if (Url.Host.EndsWith(tld, StringComparison.InvariantCultureIgnoreCase))
 {
 if (tld.Length &gt; bestMatch.Length) bestMatch = tld;
 }
 }
 if (string.IsNullOrEmpty(bestMatch))
 return Url.Host; //eg http://domain.com/blah = "domain.com"

 //add the domain name onto tld
 string[] bestBits = bestMatch.Split('.');
 string[] inputBits = Url.Host.Split('.');
 int getLastBits = bestBits.Length + 1;
 bestMatch = "";
 for (int c = inputBits.Length - getLastBits; c &lt; inputBits.Length; c++)
 {
 if (bestMatch.Length &gt; 0) bestMatch += ".";
 bestMatch += inputBits[c];
 }
 return bestMatch;
 }


 static private void initializeTLD()
 {
 if (DOMAINS.Count &gt; 0) return;

 string line;
 StreamReader reader = File.OpenText("effective_tld_names.dat");
 while ((line = reader.ReadLine()) != null)
 {
 if (!string.IsNullOrEmpty(line) &amp;&amp; !line.StartsWith("//"))
 {
 DOMAINS.Add(line);
 }
 }
 reader.Close();
 }


 // This file was taken from https://publicsuffix.org/list/effective_tld_names.dat

 static public List&lt;String&gt; DOMAINS = new List&lt;String&gt;();
}
</code></pre>

}

blocks|key|5490818|text|下面是一些只提供SLD+%2B+gTLD或ccTLD扩展的代码(注意下面的例外)。我不关心DNS。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5490819|其理论依据如下：|5490820|本地主机任何少于3个令牌的内容都保持不变，例如“|5490821|”，"domain.com"，否则:最后一个令牌必须是gTLD或ccTLD扩展名。如果倒数第二个令牌的长度小于3，或者如果包含在exceptions.|unordered-list-item|5490822|Finally列表中，那么倒数第二个令牌被认为是扩展的一部分，该令牌之前的令牌被认为是|5490823|。在此之前的任何内容都被认为是子域或主机限定符，例如Www.|5490824|至于代码，短小精悍：|5490825|private+static+string+GetDomainName(string+url)
{
++++string+domain+=+new+Uri(url).DnsSafeHost.ToLower();
++++var+tokens+=+domain.Split('.');
++++if+(tokens.Length+>+2)
++++{
++++++++//Add+only+second+level+exceptions+to+the+<+3+rule+here
++++++++string[]+exceptions+=+{+"info",+"firm",+"name",+"com",+"biz",+"gen",+"ltd",+"web",+"net",+"pro",+"org"+};+
++++++++var+validTokens+=+2+%2B+((tokens[tokens.Length+-+2].Length+<+3+%7C%7C+exceptions.Contains(tokens[tokens.Length+-+2]))+?+1+:+0);
++++++++domain+=+string.Join(".",+tokens,+tokens.Length+-+validTokens,+validTokens);
++++}
++++return+domain;
}|code-block|syntax|javascript|5490826|一个明显的例外是，这不会处理2个字母的域名。因此，如果您足够幸运地拥有ab.com，那么您需要稍微修改一下代码。对于我们这些普通的人来说，这段代码几乎涵盖了所有的gTLD和ccTLD，除了一些非常奇特的东西。|5490827|entityMap^0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|X|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Y|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Z|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|10|8|@]|9|@]|A|$]]|$1|I|3|J|5|H|7|11|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|12|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|A|$]]|$1|O|3|P|5|Q|7|14|8|@]|9|@]|A|$R|S]]|$1|T|3|U|5|6|7|15|8|@]|9|@]|A|$]]|$1|V|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|W|$]]

Below is some code that will give just the SLD plus gTLD or ccTLD extension (note the exception below). I do not care about DNS.

The theory is as follows:

<ul>
<li>Anything under 3 tokens stays as is e.g. "localhost", "domain.com", otherwise: The last token must be a gTLD or ccTLD extension. </li>
<li>The penultimate token is considered part of the extension if it's length &lt; 3 OR if included in a list of exceptions.</li>
<li>Finally the token before that one is considered the SLD. Anything before that is considered a subdomain or a host qualifier, e.g. Www.</li>
</ul>

As for the code, short &amp; sweet:

<pre><code>private static string GetDomainName(string url)
{
 string domain = new Uri(url).DnsSafeHost.ToLower();
 var tokens = domain.Split('.');
 if (tokens.Length &gt; 2)
 {
 //Add only second level exceptions to the &lt; 3 rule here
 string[] exceptions = { "info", "firm", "name", "com", "biz", "gen", "ltd", "web", "net", "pro", "org" }; 
 var validTokens = 2 + ((tokens[tokens.Length - 2].Length &lt; 3 || exceptions.Contains(tokens[tokens.Length - 2])) ? 1 : 0);
 domain = string.Join(".", tokens, tokens.Length - validTokens, validTokens);
 }
 return domain;
}
</code></pre>

The obvious exception is that this will not deal with 2-letter domain names. So if you're lucky enough to own ab.com you'll need to adapt the code slightly. For us mere mortals this code will cover just about every gTLD and ccTLD, minus a few very exotic ones.

blocks|key|5490972|text|使用Nager.PublicSuffix|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5490973|安装-package+Nager.PublicSuffix|offset|length|style|BOLD|5490974|var+domainParser+=+new+DomainParser(new+WebTldRuleProvider());

var+domainName+=+domainParser.Get("sub.test.co.uk");
//domainName.Domain+=+"test";
//domainName.Hostname+=+"sub.test.co.uk";
//domainName.RegistrableDomain+=+"test.co.uk";
//domainName.SubDomain+=+"sub";
//domainName.TLD+=+"co.uk";|code-block|syntax|javascript|5490975|entityMap^0|0|0|T|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@$D|Q|E|R|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|S|8|@]|9|@]|A|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Use Nager.PublicSuffix

install-package Nager.PublicSuffix

<pre><code>var domainParser = new DomainParser(new WebTldRuleProvider());

var domainName = domainParser.Get("sub.test.co.uk");
//domainName.Domain = "test";
//domainName.Hostname = "sub.test.co.uk";
//domainName.RegistrableDomain = "test.co.uk";
//domainName.SubDomain = "sub";
//domainName.TLD = "co.uk";
</code></pre>

blocks|key|4072416|text|我认为你对什么是“域名”存在误解--通常情况下没有“纯域名”这样的东西--如果你想得到一致的结果，你就需要定义这个东西。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4072417|你只是想去掉"www“这部分吗？然后有另一个版本，它剥离了顶级域(例如，去掉".com“或".co.uk”等部件？)另一个答案提到了拆分(“.”)-如果你想手动排除主机名的特定部分，你需要使用类似这样的东西，.NET框架中没有任何东西可以完全满足你的要求-你需要自己实现这些东西。|4072418|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

I think you are displaying a misunderstanding of what constitutes a "domain name" - there is no such thing as a "pure domain name" in common usage - this is something you will need to define if you want consistent results. 
Do you just want to strip off the "www" part?
And then have another version which strips off the top level domain (eg. strip off the ".com" or the ".co.uk" etc parts?)
Another answer mentions split(".") - you will need to use something like this if you want to exclude specific parts of the hostname manually, there's nothing within the .NET framework to meet your requirements exactly - you'll need to implement these things yourself.

blocks|key|5490998|text|我想出了以下解决方案(使用Linq)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5490999|++++public+string+MainDomainFromHost(string+host)
++++{
++++++++string[]+parts+=+host.Split('.');
++++++++if+(parts.Length+<=+2)
++++++++++++return+host;+//+host+is+probably+already+a+main+domain
++++++++if+(parts[parts.Length+-+1].All(char.IsNumber))
++++++++++++return+host;+//+host+is+probably+an+IPV4+address
++++++++if+(parts[parts.Length+-+1].Length+==+2+&&+parts[parts.Length+-+2].Length+==+2)
++++++++++++return+string.Join(".",+parts.TakeLast(3));+//+this+is+the+case+for+co.uk,+co.in,+etc...
++++++++return+string.Join(".",+parts.TakeLast(2));+//+all+others,+take+only+the+last+2
++++}|code-block|syntax|javascript|5491000|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I came up with the below solution (using Linq) :

<pre><code> public string MainDomainFromHost(string host)
 {
 string[] parts = host.Split('.');
 if (parts.Length &lt;= 2)
 return host; // host is probably already a main domain
 if (parts[parts.Length - 1].All(char.IsNumber))
 return host; // host is probably an IPV4 address
 if (parts[parts.Length - 1].Length == 2 &amp;&amp; parts[parts.Length - 2].Length == 2)
 return string.Join(".", parts.TakeLast(3)); // this is the case for co.uk, co.in, etc...
 return string.Join(".", parts.TakeLast(2)); // all others, take only the last 2
 }
</code></pre>

blocks|key|1961863|text|是的，我在这里发布了解决方案：http://pastebin.com/raw.php?i=raxNQkCF|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1961864|如果您想删除扩展，只需添加|1961865|if+(url.indexof(".")>-1)+{url+=+url.substring(0,+url.indexof("."))}|style|CODE|1961866|entityMap|0|LINK|mutability|MUTABLE|url|http://pastebin.com/raw.php?i=raxNQkCF^0|F|12|0|0|0|0|1V|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@$A|S|B|T|1|U]]|C|$]]|$1|D|3|E|5|6|7|V|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|W|8|@$A|X|B|Y|H|I]]|9|@]|C|$]]|$1|J|3|-4|5|6|7|Z|8|@]|9|@]|C|$]]]|K|$L|$5|M|N|O|C|$P|Q]]]]

Yes, ive posted the solution here: <a href="http://pastebin.com/raw.php?i=raxNQkCF" rel="nofollow">http://pastebin.com/raw.php?i=raxNQkCF</a>

If you want to remove the extension just add 

<code>if (url.indexof(".")&gt;-1) {url = url.substring(0, url.indexof("."))}</code>

blocks|key|1962008|text|Uri的主机总是返回域(www.google.com)，包括标签(www)和顶级域(com)。但通常你会想要提取中间的部分。很简单，我就是这么做的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1962009|Uri+uri;
bool+result+=+Uri.TryCreate(returnUri,+UriKind.Absolute,+out+uri);
if+(result+==+false)
++++return+false;

//if+you+are+sure+it's+not+"localhost"
string+domainParts+=+uri.Host.Split('.');
string+topLevel+=+domainParts[domainParts.Length+-+1]
string+hostBody+=+domainParts[domainParts.Length+-+2]
string+label+=+domainParts[domainParts.Length+-+3]|code-block|syntax|javascript|1962010|但您确实需要检查domainParts.length，因为给定的uri通常类似于"google.com“。|1962011|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Uri's Host always returns domain (www.google.com), including a label (www) and a top-level domain (com). But often you would want to extract the middle bit. Simply I do

<pre><code>Uri uri;
bool result = Uri.TryCreate(returnUri, UriKind.Absolute, out uri);
if (result == false)
 return false;

//if you are sure it's not "localhost"
string domainParts = uri.Host.Split('.');
string topLevel = domainParts[domainParts.Length - 1]
string hostBody = domainParts[domainParts.Length - 2]
string label = domainParts[domainParts.Length - 3]
</code></pre>

But you do need to check domainParts.length, as often the given uri is like "google.com".

blocks|key|1598219|text|我为自己找到了一个解决方案，这就是不使用任何TLD或其他东西。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1598220|它利用了所谓的主机名在主机中的事实-+Uri的一部分总是在倒数第二个位置。子域总是在名称的前面，TLD总是在它的后面。|1598221|请看这里：|1598222|private+static+string+GetNameFromHost(string+host)
{
++++if+(host.Count(f+=>+f+==+'.')+==+1)
++++{
++++++++return+host.Split('.')[0];
++++}
++++else
++++{
++++++++var+_list+=+host.Split('.').ToList();
++++++++return+_list.ElementAt(_list.Count+-+2);
++++}
}|code-block|syntax|javascript|1598223|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|O|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|P|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I found a solution for myself and this is not using any TLDs or stuff.

It uses the fact that the so called hostname is in the Host-Part of an Uri always at the second last position. Subdomains are always in front of the name and the TLD is always behind it.

See here:

<pre><code>private static string GetNameFromHost(string host)
{
 if (host.Count(f =&gt; f == '.') == 1)
 {
 return host.Split('.')[0];
 }
 else
 {
 var _list = host.Split('.').ToList();
 return _list.ElementAt(_list.Count - 2);
 }
}
</code></pre>

blocks|key|4072432|text|由于域名的种类繁多，而且没有你所描述的构成“纯域名”的任何真正的权威列表，我在过去只是求助于使用Uri.Host。为了避免www.google.com和google.com显示为两个不同的域的情况，我经常采取剥离www的方法。从包含它的所有域，因为它几乎保证(几乎)指向相同的站点。这确实是唯一一种简单的方法，可以在不丢失某些数据的情况下完成此操作。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4072433|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Because of the numerous variations in domain names and the non-existence of any real authoritative list of what constitutes a "pure domain name" as you describe, I've just resorted to using Uri.Host in the past. To avoid cases where www.google.com and google.com show up as two different domains, I've often resorted to stripping the www. from all domains that contain it, since it's almost guaranteed (ALMOST) to point to the same site. It's really the only simple way to do it without risking losing some data.

blocks|key|5490899|text|string+domain+=+new+Uri(HttpContext.Current.Request.Url.AbsoluteUri).GetLeftPart(UriPartial.Authority);|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|5490900|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>string domain = new Uri(HttpContext.Current.Request.Url.AbsoluteUri).GetLeftPart(UriPartial.Authority);
</code></pre>

I am trying to extract just the domain name from a URL string. I almost have it... I am using URI

I have a string.. my first thought was to use Regex but then i decided to use URI class

<a href="http://www.google.com/url?sa=t&amp;source=web&amp;ct=res&amp;cd=1&amp;ved=0CAgQFjAA&amp;url=http://www.test.com/&amp;rct=j&amp;q=test&amp;ei=G2phS-HdJJWTjAfckvHJDA&amp;usg=AFQjCNFSEAztaqtkaIvEzxmRm2uOARn1kQ" rel="noreferrer">http://www.google.com/url?sa=t&amp;source=web&amp;ct=res&amp;cd=1&amp;ved=0CAgQFjAA&amp;url=http://www.test.com/&amp;rct=j&amp;q=test&amp;ei=G2phS-HdJJWTjAfckvHJDA&amp;usg=AFQjCNFSEAztaqtkaIvEzxmRm2uOARn1kQ</a>

I need to convert the above to google.com and google without the www

I did the following

<pre><code>Uri test = new Uri(referrer);
log.Info("Domain part : " + test.Host);
</code></pre>

Basically this returns www.google.com .... i would like to try and return 2 forms if possible... as mentioned...

google.com
and google

Is this possible with URI?

Get just the domain name from a URL?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我正在尝试从URL字符串中提取域名。我就快成功了..。我正在使用URI我有一根绳子..。我的第一个想法是使用正则表达式，但后来我决定使用URI类我需要转换以上到google.com和谷歌没有www我做了以下工作Uri test = new Uri(referrer);log.Info("Domain part : " + test.Host);基本上，这将返回www.google.com ....

问是否仅从URL获取域名？
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回答 13

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问是否仅从URL获取域名？EN

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问是否仅从URL获取域名？
EN