bool IsGoodUrl = Uri.IsWellFormedUriString(url, UriKind.Absolute);

Uri nUrl = null;
if (Uri.TryCreate(url, UriKind.Absolute, out nUrl))
{
    url = nUrl.ToString();
}

if((!string.IsNullOrEmpty(TXBProductionURL.Text)) && (Uri.IsWellFormedUriString(TXBProductionURL.Text, UriKind.Absolute)))
{
     // assign as valid URL
     isValidProductionURL = true;

}

public static bool Url(string p_strValue)
{
    if (Uri.IsWellFormedUriString(p_strValue, UriKind.RelativeOrAbsolute))
    {
        Uri l_strUri = new Uri(p_strValue);
        return (l_strUri.Scheme == Uri.UriSchemeHttp || l_strUri.Scheme == Uri.UriSchemeHttps);
    }
    else
    {
        return false;
    }
}