C#、Asp.net 使用 WebClient Get Post（同步、异步）

using System;
using System.Globalization;
using System.Net;
using System.Text;

namespace Test
{
public class HttpCommon
{
/// <summary>
/// Http同步Get同步请求
/// </summary>
/// <param name="url">Url地址</param>
/// <param name="encode">编码(默认UTF8)</param>
/// <returns></returns>
public static string HttpGet(string url, Encoding encode = null)
{
string result;

try
{
var webClient = new WebClient { Encoding = Encoding.UTF8 };

if (encode != null)
webClient.Encoding = encode;

result = webClient.DownloadString(url);
}
catch (Exception ex)
{
result = ex.Message;
}

return result;
}

/// <summary>
/// Http同步Get异步请求
/// </summary>
/// <param name="url">Url地址</param>
/// <param name="callBackDownStringCompleted">回调事件</param>
/// <param name="encode">编码(默认UTF8)</param>
public static void HttpGetAsync(string url,
DownloadStringCompletedEventHandler callBackDownStringCompleted = null, Encoding encode = null)
{
var webClient = new WebClient { Encoding = Encoding.UTF8 };

if (encode != null)
webClient.Encoding = encode;

if (callBackDownStringCompleted != null)
webClient.DownloadStringCompleted += callBackDownStringCompleted;

webClient.DownloadStringAsync(new Uri(url));
}

/// <summary>
///  Http同步Post同步请求
/// </summary>
/// <param name="url">Url地址</param>
/// <param name="postStr">请求Url数据</param>
/// <param name="encode">编码(默认UTF8)</param>
/// <returns></returns>
public static string HttpPost(string url, string postStr = "", Encoding encode = null)
{
string result;

try
{
var webClient = new WebClient { Encoding = Encoding.UTF8 };

if (encode != null)
webClient.Encoding = encode;

var sendData = Encoding.GetEncoding("GB2312").GetBytes(postStr);

webClient.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
webClient.Headers.Add("ContentLength", sendData.Length.ToString(CultureInfo.InvariantCulture));

var readData = webClient.UploadData(url, "POST", sendData);

result = Encoding.GetEncoding("GB2312").GetString(readData);

}
catch (Exception ex)
{
result = ex.Message;
}

return result;
}

/// <summary>
/// Http同步Post异步请求
/// </summary>
/// <param name="url">Url地址</param>
/// <param name="postStr">请求Url数据</param>
/// <param name="callBackUploadDataCompleted">回调事件</param>
/// <param name="encode"></param>
public static void HttpPostAsync(string url, string postStr = "",
UploadDataCompletedEventHandler callBackUploadDataCompleted = null, Encoding encode = null)
{
var webClient = new WebClient { Encoding = Encoding.UTF8 };

if (encode != null)
webClient.Encoding = encode;

var sendData = Encoding.GetEncoding("GB2312").GetBytes(postStr);

webClient.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
webClient.Headers.Add("ContentLength", sendData.Length.ToString(CultureInfo.InvariantCulture));

if (callBackUploadDataCompleted != null)
webClient.UploadDataCompleted += callBackUploadDataCompleted;

webClient.UploadDataAsync(new Uri(url), "POST", sendData);
}
}
}

using System;
using System.Net;
using System.Text;
using System.Web.UI;

namespace Test
{
public partial class WebForm3 : Page
{
protected void Page_Load(object sender, EventArgs e)
{
Response.Write(HttpCommon.HttpGet("http://localhost:14954/WebForm4.aspx"));                          //Get同步
HttpCommon.HttpGetAsync("http://localhost:14954/WebForm4.aspx");                                     //Get异步
HttpCommon.HttpGetAsync("http://localhost:14954/WebForm4.aspx", DownStringCompleted);                //Get异步回调

Response.Write(HttpCommon.HttpPost("http://localhost:14954/WebForm4.aspx", "post=POST"));            //Post同步
HttpCommon.HttpPostAsync("http://localhost:14954/WebForm4.aspx", "post=POST");                       //Post异步
HttpCommon.HttpPostAsync("http://localhost:14954/WebForm4.aspx", "post=POST", UploadDataCompleted);  //Post异步回调
}

private void DownStringCompleted(object sender, DownloadStringCompletedEventArgs e)
{
Response.Write(e.Result);
}

private void UploadDataCompleted(object sender, UploadDataCompletedEventArgs e)
{
Response.Write(Encoding.GetEncoding("GB2312").GetString(e.Result));
}
}
}