C# Post提交

方法一（建議）：

    /// <summary>
    /// Post提交
    /// </summary>
    /// <param name="url">訪問鏈接</param>
    /// <param name="para">參數 UserName="Name"&Pwd="123"</param>
    /// <returns></returns>
    public static string GetHtmlEx(string url,string para)
    {
        string postData = para; // 參數
        byte[] byteArray = Encoding.UTF8.GetBytes(postData);

        HttpWebRequest objWebRequest = (HttpWebRequest)WebRequest.Create(url);
        objWebRequest.Method = "POST";
        objWebRequest.ContentType = "application/x-www-form-urlencoded";
        objWebRequest.ContentLength = byteArray.Length;
        Stream newStream = objWebRequest.GetRequestStream();
        // Send the data. 
        newStream.Write(byteArray, 0, byteArray.Length); //寫入參數 
        newStream.Close();

        HttpWebResponse response = (HttpWebResponse)objWebRequest.GetResponse();
        StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.Default);
        string textResponse = sr.ReadToEnd(); // 返回的數據
        return textResponse;
    }

方法二：

    /// <summary>
    /// Post提交
    /// </summary>
    /// <param name="url">鏈接 如：www.baidu.com/login.html?UserName="1522222"&Pwd="123"</param>
    /// <param name="encoding">字符編碼方式</param>
    /// <returns></returns>
    public static String SendRequest(String url, Encoding encoding)
    {
            HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(url);
            webRequest.Method = "Post";
            HttpWebResponse webResponse = (HttpWebResponse)webRequest.GetResponse();
            StreamReader sr = new StreamReader(webResponse.GetResponseStream(), encoding);
            return sr.ReadToEnd();
    }