blocks|key|3008942|text|您可以使用当前请求的UrlReferrer属性：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3008943|Request.UrlReferrer|code-block|syntax|javascript|3008944|这将从客户端(用户代理)提供也可能不提供的请求中读取Referer+HTTP报头。|3008945|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/system.web.httprequest.urlreferrer.aspx|1|http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.36^0|A|B|0|0|0|Q|7|1|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@$A|10|B|11|1|12]]|C|$]]|$1|K|3|-4|5|6|7|13|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]|S|$5|N|O|P|C|$Q|T]]]]

You could use the <a href="http://msdn.microsoft.com/en-us/library/system.web.httprequest.urlreferrer.aspx" rel="noreferrer">UrlReferrer</a> property of the current request:

<pre><code>Request.UrlReferrer
</code></pre>

This will read the <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.36" rel="noreferrer">Referer</a> HTTP header from the request which may or may not be supplied by the client (user agent).

blocks|key|3009025|text|Request.Headers["Referer"]|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|3009026|解释|unstyled|3009027|如果referer+HTTP报头格式不正确，Request.UrlReferer属性将抛出System.UriFormatException+(这是可能的，因为它通常不在您的控制之下)。|offset|length|style|CODE|3009028|因此，Request.UrlReferer属性不是100%25可靠的-它可能包含无法解析到Uri类中的数据。要确保该值始终可读，请改用Request.Headers["Referrer"]。|3009029|至于像其他人在这里建议的那样使用Request.ServerVariables，请按照MSDN：|3009030|Request.ServerVariables集合|BOLD|3009031|3009032|+ServerVariables集合检索预定环境变量的值和请求标头信息。|blockquote|3009033|3009034|3009035|Request.Headers属性|3009036|3009037|获取HTTP头的集合。|3009038|3009039|3009040|Request.Headers是比Request.ServerVariables更好的选择，因为Request.ServerVariables包含所有的环境变量和头部，而Request.Headers是一个更短的列表，它只包含头部。|3009041|因此，最可靠的解决方案是使用Request.Headers集合直接读取值。但是，如果您要在表单上显示该值，请注意Microsoft关于HTML编码值的警告。|3009042|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.microsoft.com/en-us/dotnet/api/system.web.httprequest.urlreferrer?view=netframework-4.8^0|0|0|M|I|19|P|M|I|0|0|3|I|17|3|1T|R|0|G|N|0|0|P|0|0|0|0|0|0|H|0|0|0|0|0|0|F|H|N|1C|N|2D|F|0|E|F|0^^$0|@$1|2|3|4|5|6|7|1I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|1J|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|1K|8|@$I|1L|J|1M|K|L]|$I|1N|J|1O|K|L]]|9|@$I|1P|J|1Q|1|1R]]|A|$]]|$1|M|3|N|5|F|7|1S|8|@$I|1T|J|1U|K|L]|$I|1V|J|1W|K|L]|$I|1X|J|1Y|K|L]]|9|@]|A|$]]|$1|O|3|P|5|F|7|1Z|8|@$I|20|J|21|K|L]]|9|@]|A|$]]|$1|Q|3|R|5|F|7|22|8|@$I|23|J|24|K|S]]|9|@]|A|$]]|$1|T|3|-4|5|F|7|25|8|@]|9|@]|A|$]]|$1|U|3|V|5|W|7|26|8|@]|9|@]|A|$]]|$1|X|3|-4|5|F|7|27|8|@]|9|@]|A|$]]|$1|Y|3|-4|5|F|7|28|8|@]|9|@]|A|$]]|$1|Z|3|10|5|F|7|29|8|@$I|2A|J|2B|K|S]]|9|@]|A|$]]|$1|11|3|-4|5|F|7|2C|8|@]|9|@]|A|$]]|$1|12|3|13|5|W|7|2D|8|@]|9|@]|A|$]]|$1|14|3|-4|5|F|7|2E|8|@]|9|@]|A|$]]|$1|15|3|-4|5|F|7|2F|8|@]|9|@]|A|$]]|$1|16|3|17|5|F|7|2G|8|@$I|2H|J|2I|K|L]|$I|2J|J|2K|K|L]|$I|2L|J|2M|K|L]|$I|2N|J|2O|K|L]]|9|@]|A|$]]|$1|18|3|19|5|F|7|2P|8|@$I|2Q|J|2R|K|L]]|9|@]|A|$]]|$1|1A|3|-4|5|F|7|2S|8|@]|9|@]|A|$]]]|1B|$1C|$5|1D|1E|1F|A|$1G|1H]]]]

<pre><code>Request.Headers[&quot;Referer&quot;]
</code></pre>
<h1>Explanation</h1>
<h3>The <a href="https://docs.microsoft.com/en-us/dotnet/api/system.web.httprequest.urlreferrer?view=netframework-4.8" rel="noreferrer"><code>Request.UrlReferer</code></a> property will throw a <code>System.UriFormatException</code> if the referer HTTP header is malformed (which can happen since it is not usually under your control).</h3>
Therefore, the <code>Request.UrlReferer</code> property is not 100% reliable - it may contain data that cannot be parsed into a <code>Uri</code> class. To ensure the value is always readable, use <code>Request.Headers[&quot;Referrer&quot;]</code> instead.
As for using <code>Request.ServerVariables</code> as others here have suggested, per MSDN:
Request.ServerVariables Collection
<blockquote>
The ServerVariables collection retrieves the values of predetermined environment variables and request header information.
</blockquote>
Request.Headers Property
<blockquote>
Gets a collection of HTTP headers.
</blockquote>
<code>Request.Headers</code> is a better choice than <code>Request.ServerVariables</code>, since <code>Request.ServerVariables</code> contains all of the environment variables as well as the headers, where <code>Request.Headers</code> is a much shorter list that only contains the headers.
So the most reliable solution is to use the <code>Request.Headers</code> collection to read the value directly. Do heed Microsoft's warnings about HTML encoding the value if you are going to display it on a form, though.

blocks|key|3222957|text|使用Request.UrlReferrer属性。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3222958|在场景下面，它只是检查ServerVariables("HTTP_REFERER")属性。|3222959|entityMap^0|2|J|0|B|V|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|P|8|@]|D|@]|E|$]]]|I|$]]

Use the <code>Request.UrlReferrer</code> property.

Underneath the scenes it is just checking the <code>ServerVariables("HTTP_REFERER")</code> property.

blocks|key|3008961|text|像这样：HttpRequest.UrlReferrer+Property+|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3008962|Uri+myReferrer+=+Request.UrlReferrer;
string+actual+=+myReferrer.ToString();|code-block|syntax|javascript|3008963|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/system.web.httprequest.urlreferrer.aspx^0|4|X|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Like this: <a href="http://msdn.microsoft.com/en-us/library/system.web.httprequest.urlreferrer.aspx" rel="noreferrer">HttpRequest.UrlReferrer Property </a>

<pre><code>Uri myReferrer = Request.UrlReferrer;
string actual = myReferrer.ToString();
</code></pre>

blocks|key|3009127|text|我使用的是.Net+Core2MVC，这对我来说很有效(以获得预览页面)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3009128|HttpContext.Request.Headers["Referer"];|code-block|syntax|javascript|3009129|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'm using .Net Core 2 mvc,
this one work for me ( to get the previews page) :

<pre><code>HttpContext.Request.Headers["Referer"];
</code></pre>

blocks|key|290083|text|由于谷歌在搜索C#+Web+API+Referrer时会把你带到这篇文章，这里是交易：Web+API使用与普通Request不同类型的MVC+Request，称为HttpRequestMessage，它不包括UrlReferrer。由于正常的Web+API请求不包括此信息，因此如果您确实需要此信息，则必须让您的客户端不遗余力地将其包括在内。尽管您可以将其作为API+Object的一部分，但更好的方法是使用Headers。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|290084|首先，您可以扩展HttpRequestMessage以提供UrlReferrer()方法：|290085|public+static+string+UrlReferrer(this+HttpRequestMessage+request)
{
++++return+request.Headers.Referrer+==+null+?+"unknown"+:+request.Headers.Referrer.AbsoluteUri;
}|code-block|syntax|javascript|290086|然后，您的客户端需要将Referrer+Header设置为其API+Request|290087|//+Microsoft.AspNet.WebApi.Client
client.DefaultRequestHeaders.Referrer+=+new+Uri(url);|290088|现在，您可以从Web+API访问Web+API+Request中的推荐人数据，如下所示|290089|Request.UrlReferrer();|290090|entityMap^0|7|J|17|7|1J|7|1V|B|29|I|2W|B|3D|7|50|A|5O|7|0|8|I|T|D|0|0|B|F|U|B|0|0|7|7|G|F|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]|$9|11|A|12|B|C]|$9|13|A|14|B|C]|$9|15|A|16|B|C]|$9|17|A|18|B|C]|$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1F|8|@$9|1G|A|1H|B|C]|$9|1I|A|1J|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|1K|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|1L|8|@$9|1M|A|1N|B|C]|$9|1O|A|1P|B|C]]|D|@]|E|$]]|$1|O|3|P|5|J|7|1Q|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|1R|8|@$9|1S|A|1T|B|C]|$9|1U|A|1V|B|C]]|D|@]|E|$]]|$1|S|3|T|5|J|7|1W|8|@]|D|@]|E|$K|L]]|$1|U|3|-4|5|6|7|1X|8|@]|D|@]|E|$]]]|V|$]]

Since Google takes you to this post when searching for <code>C# Web API Referrer</code> here's the deal: <code>Web API</code> uses a different type of <code>Request</code> from normal <code>MVC Request</code> called <code>HttpRequestMessage</code> which does not include <code>UrlReferrer</code>. Since a normal <code>Web API</code> request does not include this information, if you really need it, you must have your clients go out of their way to include it. Although you could make this be part of your <code>API Object</code>, a better way is to use <code>Headers</code>.

First, you can extend <code>HttpRequestMessage</code> to provide a <code>UrlReferrer()</code> method:

<pre><code>public static string UrlReferrer(this HttpRequestMessage request)
{
 return request.Headers.Referrer == null ? "unknown" : request.Headers.Referrer.AbsoluteUri;
}
</code></pre>

Then your clients need to set the <code>Referrer Header</code> to their <code>API Request</code>:

<pre><code>// Microsoft.AspNet.WebApi.Client
client.DefaultRequestHeaders.Referrer = new Uri(url);
</code></pre>

And now the <code>Web API Request</code> includes the referrer data which you can access like this from your <code>Web API</code>:

<pre><code>Request.UrlReferrer();
</code></pre>

blocks|key|288235|text|string+referrer+=+HttpContext.Current.Request.UrlReferrer.ToString();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|288236|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 referrer = HttpContext.Current.Request.UrlReferrer.ToString();
</code></pre>

blocks|key|290955|text|有时你必须像这样给出所有的链接|type|unstyled|depth|inlineStyleRanges|entityRanges|data|290956|System.Web.HttpContext.Current.Request.UrlReferrer.ToString();|code-block|syntax|javascript|290957|(当“当前”未建立时，在选项中)|290958|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|$]]

Sometime you must to give all the link like this 

<pre><code>System.Web.HttpContext.Current.Request.UrlReferrer.ToString();
</code></pre>

(in option when "Current" not founded)

blocks|key|290969|text|属于其他回复，我添加了获取null的条件子句。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|290970|string+ComingUrl+=+"";
if+(Request.UrlReferrer+!=+null)
{
++++ComingUrl+=+System.Web.HttpContext.Current.Request.UrlReferrer.ToString();
}
else
{
++++ComingUrl+=+"Direct";+//+Your+code
}|code-block|syntax|javascript|290971|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|$]]

Belonging to other reply, I have added condition clause for getting null.

<pre><code>string ComingUrl = "";
if (Request.UrlReferrer != null)
{
 ComingUrl = System.Web.HttpContext.Current.Request.UrlReferrer.ToString();
}
else
{
 ComingUrl = "Direct"; // Your code
}
</code></pre>

blocks|key|3009194|text|使用.NET核心或.NET+5时，我建议您这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3009195|httpContext.Request.Headers.TryGetValue("Referer",+out+var+refererHeader)|code-block|syntax|javascript|3009196|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|$]]

Using .NET Core or .NET 5 I would recommend this:
<pre><code>httpContext.Request.Headers.TryGetValue(&quot;Referer&quot;, out var refererHeader)
</code></pre>

I'm looking for a quick, easy and reliable way of getting the browser's HTTP Referrer in ASP.Net (C#). I know the HTTP Referrer itself is unreliable, but I do want a reliable way of getting the referrer if it is present.

Getting the HTTP Referrer in ASP.NET

我正在寻找一种快速、简单和可靠的方法来在ASP.Net (C#)中获得浏览器的HTTP Referrer。我知道HTTP引用本身是不可靠的，但我确实想要一个可靠的方法来获取引用，如果它存在的话。

问在ASP.NET中获取
EN

回答 10

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问在ASP.NET中获取EN

回答 10

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问在ASP.NET中获取
EN