首页 > 代码库 > C# HTTP请求GET,POST

C# HTTP请求GET,POST

转自原文 【C#】HTTP请求GET,POST

 

HTTP定义了与服务器交互的不同方法,基本方法有GET,POST,PUT,DELETE,分别对于查,该,增,删。一般情况下我们只用到GET和POST,其他两种都也可以用GET和POST来实现,很多浏览器也只实现了GET和POST两种方法

  GET:用户获取信息

    安全的:不会对服务器上的数据进行修改,和破坏

    幂等的:相同的请求所返回的结果相同

    参数是通过Url来传输,接在Url后面中间用?分开,不同参数之间用&分开,下面表示传递两个参数param1和param2,值为value1和value2

      http://songurl/index.htm?param1=value1&param2=value2

    通过上面可以看到,GET请求数据在隐私方面又是不安全的,因为Url上的信息可以直接让用户看到,这样不利于隐私保护

  POST:用于更新数据

    传递的数据对用户隐藏,封装在包里,具体看演示

    有时候请求会重定向,但我们就需要从重定向url获取东西,这时可以设置重定向禁用,你就可以从headers的Location属性中获取重定向地址

      request.AllowAutoRedirect = false;

      string[] values = request.Headers.GetValues("Location");

下面是辅助类的定义

 

public class HttpHelper        {            /// <summary>              /// 创建GET方式的HTTP请求              /// </summary>              public static HttpWebResponse CreateGetHttpResponse(string url, int timeout, string userAgent, CookieCollection cookies)            {                HttpWebRequest request = null;                if (url.StartsWith("https", StringComparison.OrdinalIgnoreCase))                {                    //对服务端证书进行有效性校验(非第三方权威机构颁发的证书,如自己生成的,不进行验证,这里返回true)                    ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);                    request = WebRequest.Create(url) as HttpWebRequest;                    request.ProtocolVersion = HttpVersion.Version10;    //http版本,默认是1.1,这里设置为1.0                }                else                {                    request = WebRequest.Create(url) as HttpWebRequest;                }                request.Method = "GET";                                //设置代理UserAgent和超时                //request.UserAgent = userAgent;                //request.Timeout = timeout;                if (cookies != null)                {                    request.CookieContainer = new CookieContainer();                    request.CookieContainer.Add(cookies);                }                return request.GetResponse() as HttpWebResponse;            }                        /// <summary>              /// 创建POST方式的HTTP请求              /// </summary>              public static HttpWebResponse CreatePostHttpResponse(string url, IDictionary<string, string> parameters, int timeout, string userAgent, CookieCollection cookies)            {                HttpWebRequest request = null;                //如果是发送HTTPS请求                  if (url.StartsWith("https", StringComparison.OrdinalIgnoreCase))                {                    //ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);                    request = WebRequest.Create(url) as HttpWebRequest;                    //request.ProtocolVersion = HttpVersion.Version10;                }                else                {                    request = WebRequest.Create(url) as HttpWebRequest;                }                request.Method = "POST";                request.ContentType = "application/x-www-form-urlencoded";                //设置代理UserAgent和超时                //request.UserAgent = userAgent;                //request.Timeout = timeout;                 if (cookies != null)                {                    request.CookieContainer = new CookieContainer();                    request.CookieContainer.Add(cookies);                }                //发送POST数据                  if (!(parameters == null || parameters.Count == 0))                {                    StringBuilder buffer = new StringBuilder();                    int i = 0;                    foreach (string key in parameters.Keys)                    {                        if (i > 0)                        {                            buffer.AppendFormat("&{0}={1}", key, parameters[key]);                        }                        else                        {                            buffer.AppendFormat("{0}={1}", key, parameters[key]);                            i++;                        }                    }                    byte[] data =http://www.mamicode.com/ Encoding.ASCII.GetBytes(buffer.ToString());                    using (Stream stream = request.GetRequestStream())                    {                        stream.Write(data, 0, data.Length);                    }                }                string[] values = request.Headers.GetValues("Content-Type");                return request.GetResponse() as HttpWebResponse;            }            /// <summary>            /// 获取请求的数据            /// </summary>            public static string GetResponseString(HttpWebResponse webresponse)            {                using (Stream s = webresponse.GetResponseStream())                {                    StreamReader reader = new StreamReader(s, Encoding.UTF8);                    return reader.ReadToEnd();                }            }                        /// <summary>            /// 验证证书            /// </summary>            private static bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)            {                if (errors == SslPolicyErrors.None)                    return true;                return false;            }          }

 

C# HTTP请求GET,POST