/// <summary>
/// 创建GET方式的HTTP/HTTPS请求
/// </summary>
/// <param name="url">请求的URL</param>
/// <param name="timeout">请求的超时时间</param>
/// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>
/// <param name="requestEncoding">发送HTTP请求时所用的编码</param>
/// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>
/// <returns></returns>
public static HttpWebResponse CreateGet(string url, int?timeout = null, string userAgent = null,
CookieCollection cookies = null)
{
return(Create(url, null, "GET", requestEncoding, timeout, cookies.ToString()));
}