How to Check if a URL Exists in C#?

How to verify whether a URL exists in C#

Your code uses the WebClient class to retrieve data from the URL. However, when the user enters a stock symbol that does not exist, a runtime error is encountered. In order to solve this problem, you need a way to check if the URL is valid before trying to download it.

How to use HTTPWebRequest:

One way is to use the HttpWebRequest class. Here is an example implementation:

private bool RemoteFileExists(string url)
{
    try
    {
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
        request.Method = "HEAD";

        using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
        {
            return (response.StatusCode == HttpStatusCode.OK);
        }
    }
    catch
    {
        return false;
    }
}

This method sends an HTTP HEAD request to the URL. If the response code is 200 (OK), it means the file exists and is accessible. Otherwise, it returns false.

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