using System;

using System.Net;

using Newtonsoft.Json;

public class Program

{

​

    //

    // Checks how well a url validator does against a known list of valid and invalid Urls

    // The sample urls here are from http://formvalidation.io/validators/uri

    //  

    public static void Main()

    {                           

        VerifyUrlChecker();     

    }

​

    public static bool IsUrlValid(string url)

    {

        return UrlChecker1(url);

    }

    // From this answer: https://stackoverflow.com/a/7581824/700206

    public static bool UrlChecker1(string url)

    {

        Uri uriResult;

        bool tryCreateResult = Uri.TryCreate(url, UriKind.Absolute, out uriResult);

        if (tryCreateResult==true && uriResult!=null)

            return true;

        else

            return false;

    }

    // From this answer: https://stackoverflow.com/a/37051246/700206

    public static bool UrlChecker2(string url)

    {

        return Uri.IsWellFormedUriString("https://www.google.com", UriKind.Absolute);

    }

    public static int VerifyUrlChecker() {

        int invalidUrlsMissed = 0;

        int validUrlsMissed = 0;

        Console.WriteLine("Verifying Url Checker...");

        foreach (string url in validUrls)

        {

            if (IsUrlValid(url)==false)

            {

                invalidUrlsMissed++;

                Console.WriteLine("  Error - tested invalid, should be valid:");

                Console.WriteLine("    " + url);

            }

        }

        foreach (string url in invalidUrls)

        {

            if (IsUrlValid(url)==true)

            {

                invalidUrlsMissed++;

                Console.WriteLine("  Error - tested valid, should be invalid:");

                Console.WriteLine("    " + url);

            }

        }

        var totalErrors = invalidUrlsMissed + validUrlsMissed;

        Console.WriteLine("------------------------");

        Console.WriteLine("Urls Checked:\t\t" + (validUrls.Length + invalidUrls.Length));

        Console.WriteLine("Validation errors:\t" + totalErrors);

        return totalErrors;

    }

    static string[] validUrls = new string[] { 

        "http://foo.com/blah_blah",

        "http://foo.com/blah_blah/",    

        "http://foo.com/blah_blah_(wikipedia)",

        "http://foo.com/blah_blah_(wikipedia)_(again)",

        "http://www.example.com/wpstyle/?p=364",

        "http://?",

        "https://www.example.com/foo/?bar=baz&inga=42&quux",

        "http://✪df.ws/123",

        "http://userid:password@example.com:8080",

        "http://userid:password@example.com:8080/",

        "http://userid@example.com",

        "http://userid@example.com/",

        "http://userid@example.com:8080",

        "http://userid@example.com:8080/",  

        "http://userid:password@example.com",

        "http://userid:password@example.com/",  

        "http://142.42.1.1/",

        "http://142.42.1.1:8080/",

        "http://➡.ws/䨹",

        "http://⌘.ws",

        "http://⌘.ws/", 

        "http://foo.com/blah_(wikipedia)#cite-1",

        "http://foo.com/blah_(wikipedia)_blah#cite-1",

        "http://foo.com/unicode_(✪)_in_parens",

        "http://foo.com/(something)?after=parens",

        "http://☺.damowmow.com/",

        "http://code.google.com/events/#&product=browser",

        "http://j.mp",

        "http://foo.bar/?q=Test%20URL-encoded%20stuff",

        "http://مثال.إختبار",

        "http://例子.测试",

        "http://उदाहरण.परीक्ष",

        "http://-.~_!$&'()*+,;=:%40:80%2f::::::@example.com",

        "http://1337.net",

        "http://a.b-c.de",  

        "http://223.255.255.254"

    };

    static string[] invalidUrls = new string[] { 

        "http://",

        "http://.", 

        "http://..",

        "http://../",

        "http://?",

        "http://??",    

        "http://??/",

        "http://#",

        "http://##",    

        "http://##/",

        "http://foo.bar?q=Spaces should be encoded",

        "//",

        "//a",  

        "///a", 

        "///",

        "http:///a",

        "foo.com",

        "rdar://1234",

        "h://test",

        "http:// shouldfail.com",

        ":// should fail",

        "http://foo.bar/foo(bar)baz quux",

        "ftps://foo.bar/",

        "http://-error-.invalid/",

        "http://a.b--c.de/",

        "http://-a.b.co",

        "http://a.b-.co",

        "http://0.0.0.0",

        "http://10.1.1.0",  

        "http://10.1.1.255",    

        "http://224.1.1.1",

        "http://1.1.1.1.1",

        "http://123.123.123",   

        "http://3628126748",

        "http://.www.foo.bar/", 

        "http://www.foo.bar./",

        "http://.www.foo.bar./",    

        "http://10.1.1.1",

        "http://10.1.1.254"

    };  

}