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    <p>These solutions are pretty good, but they are forgetting that there may be other status codes than 200 OK. This is a solution that I've used on production environments for status monitoring and such. </p> <p>If there is a url redirect or some other condition on the target page, the return will be true using this method. Also, GetResponse() will throw an exception and hence you will not get a StatusCode for it. You need to trap the exception and check for a ProtocolError.</p> <p>Any 400 or 500 status code will return false. All others return true. This code is easily modified to suit your needs for specific status codes.</p> <pre><code>/// &lt;summary&gt; /// This method will check a url to see that it does not return server or protocol errors /// &lt;/summary&gt; /// &lt;param name="url"&gt;The path to check&lt;/param&gt; /// &lt;returns&gt;&lt;/returns&gt; public bool UrlIsValid(string url) { try { HttpWebRequest request = HttpWebRequest.Create(url) as HttpWebRequest; request.Timeout = 5000; //set the timeout to 5 seconds to keep the user from waiting too long for the page to load request.Method = "HEAD"; //Get only the header information -- no need to download any content using (HttpWebResponse response = request.GetResponse() as HttpWebResponse) { int statusCode = (int)response.StatusCode; if (statusCode &gt;= 100 &amp;&amp; statusCode &lt; 400) //Good requests { return true; } else if (statusCode &gt;= 500 &amp;&amp; statusCode &lt;= 510) //Server Errors { //log.Warn(String.Format("The remote server has thrown an internal error. Url is not valid: {0}", url)); Debug.WriteLine(String.Format("The remote server has thrown an internal error. Url is not valid: {0}", url)); return false; } } } catch (WebException ex) { if (ex.Status == WebExceptionStatus.ProtocolError) //400 errors { return false; } else { log.Warn(String.Format("Unhandled status [{0}] returned for url: {1}", ex.Status, url), ex); } } catch (Exception ex) { log.Error(String.Format("Could not test url {0}.", url), ex); } return false; } </code></pre>
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    1. POC# How can I check if a URL exists/is valid?
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    1. USjsmith
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    1. COI would add that some status codes in the 3xx range will actually cause an error to be thrown e.g. 304 Not Modified in which case you should be handling that in your catch block
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    2. COJust experienced a pull-your-hair-out problem with this approach: `HttpWebRequest` doesn't like it if you don't `.Close()` the `response` object before you try to download anything else. Took hours to find that one!
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    3. CO`HttpWebResponse` object **should be enclosed in `using` block** since it implements `IDisposable` which will also ensure closing the connection. This might cause problems as @jbeldock, has faced.
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