I made a LinkChecker program which checks URLs from a text file and outputs status into another file like this:http://valid-url.com;OKhttp://invalid-url.com;The remote server returned an error: (404) Not Found.I have about 1400 URLs in the input file and it takes about 12 minutes to run. I made it work. In what ways can I achieve rightness and fastness?public class LinkChecker{    static void Main()    {        string line = string.Empty;        string inputFile = @D:\tmp\links.txt;        StreamReader file = new StreamReader(inputFile);        string outputFile = @D:\tmp\out.txt;        ClearOutputFile(outputFile);        while(!string.IsNullOrEmpty(line = file.ReadLine()))        {            string currentUrlAndStatus = CheckURL(line);            if(!string.IsNullOrEmpty(currentUrlAndStatus))            {                WriteToFile(currentUrlStatus, outputFile);            }        }    }    private static string CheckURL(string url)    {        string status = string.Empty;        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);        request.Method = HEAD;        request.Proxy = null;        try        {            using(HttpWebResponse response = (HttpWebResponse)request.GetResponse())            {                status = response.StatusCode.ToString();            }        }        catch (WebException ex)        {            status = ex.Status;        }        return url + ; + status;    }    private static void ClearOutputFile(string file)    {        using (Filestream fileStream = File.Open(file, FileMode.Open)        {            fileStream.SetLength(0);        }    }    private static void WriteToFile(string message, string filename)    {        using(var writer = new StreamWriter(filename, true))        {            writer.WriteLine(message);        }    }}
How can I better my URL checker program?
c#;http;url