C# 实现HTTP不同方法的请求示例

1、不带参数的POST请求

public static string Post(string url)  
{  
    string result = "";  
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);  
    req.Method = "POST";  
    HttpWebResponse resp = (HttpWebResponse)req.GetResponse();  
    Stream stream = resp.GetResponseStream();  
    //获取内容  
    using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))  
    {  
        result = reader.ReadToEnd();  
    }  
    return result;  
}  

2、带参数的POST请求

public static string Post(string url,Dictionary<string,string> dic)  
{  
    string result = "";  
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);  
    req.Method = "POST";  
    req.ContentType = "application/x-www-form-urlencoded";  
    #region 添加Post 参数  
    StringBuilder builder = new StringBuilder();  
    int i = 0;  
    foreach (var item in dic)  
    {  
        if (i > 0)  
            builder.Append("&");  
        builder.AppendFormat("{0}={1}", item.Key, item.Value);  
        i++;  
    }  
    byte[] data = Encoding.UTF8.GetBytes(builder.ToString());  
    req.ContentLength = data.Length;  
    using (Stream reqStream = req.GetRequestStream())  
    {  
        reqStream.Write(data, 0, data.Length);  
        reqStream.Close();  
    }  
    #endregion  
    HttpWebResponse resp = (HttpWebResponse)req.GetResponse();  
    Stream stream = resp.GetResponseStream();  
    //获取响应内容  
    using (StreamReader reader = new StreamReader(stream, Encoding.UTF8))  
    {  
        result = reader.ReadToEnd();  
    }  
    return result;  
}  

3、不带参数的GET请求

public static string Get(string url)  
{  
    string result = "";  
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);  
    HttpWebResponse resp = (HttpWebResponse)req.GetResponse();  
    Stream stream = resp.GetResponseStream();  
    try  
    {  
        //获取内容  
        using (StreamReader reader = new StreamReader(stream))  
        {  
            result = reader.ReadToEnd();  
        }  
    }  
    finally  
    {  
        stream.Close();  
    }  
    return result;  
} 

4、带参数的GET请求

public static string Get(string url, Dictionary<string, string> dic)  
{  
    string result = "";  
    StringBuilder builder = new StringBuilder();  
    builder.Append(url);  
    if (dic.Count > 0)  
    {  
        builder.Append("?");  
        int i = 0;  
        foreach (var item in dic)  
        {  
            if (i > 0)  
                builder.Append("&");  
            builder.AppendFormat("{0}={1}", item.Key, item.Value);  
            i++;  
        }  
    }  
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(builder.ToString());  
    //添加参数  
    HttpWebResponse resp = (HttpWebResponse)req.GetResponse();  
    Stream stream = resp.GetResponseStream();  
    try  
    {  
        //获取内容  
        using (StreamReader reader = new StreamReader(stream))  
        {  
            result = reader.ReadToEnd();  
        }  
    }  
    finally  
    {  
        stream.Close();  
    }  
    return result;  
}  

5、自定义HTTP请求头

HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);  
req.Method = "GET";  
req.Headers["Accept-Language"] = "zh-CN,zh;q=0.8";  
req.Referer = "https://www.baidu.com/";  
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();  
Stream stream = resp.GetResponseStream();  string result = "";  //注意，此处使用的编码是：gb2312  //using (StreamReader reader = new StreamReader(stream, Encoding.Default))  using (StreamReader reader = new StreamReader(stream, Encoding.GetEncoding("gb2312")))  
{  
    result = reader.ReadToEnd();  
}