官方文档说明：https://mp.weixin.qq.com/wiki?t=resource/res_main&id=mp1421140183&token=&lang=zh_CN
具体实现方法如下：
类WXApi.cs:
#region 获取access_token
/// <summary>
/// 获取access_token
/// </summary>
public static string GetAccessToken(string appid, string secret)
{
string strJson = HttpRequestUtil.RequestUrl(string.Format("https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={0}&secret={1}", appid, secret));
return Tools.GetJsonValue(strJson, "access_token");
}
#endregion
类AdminUtil.cs:
#region 获取access_token
/// <summary>
/// 获取access_token
/// </summary>
public static string GetAccessToken()
{
string access_token = WXModel.access_token;
string AppID = WXModel.AppID;
string AppSecret = WXModel.AppSecret; //获取session 中的 access_token
if (string.IsNullOrWhiteSpace(access_token)) //尚未保存过access_token
{
access_token = WXApi.GetAccessToken(AppID, AppSecret);
}
else
{
if (WXApi.TokenExpired(access_token)) //access_token过期
{
access_token = WXApi.GetAccessToken(AppID, AppSecret);
}
else
{
return access_token;
}
}
//更新access_token
HttpContext.Current.Application["access_token"] = access_token;
return access_token;
}
#endregion
Controller:
public void GetAccessToken()
{
string access_token = AdminUtil.GetAccessToken();
Response.Write("access_token=" + access_token);
}
工具类：
public static class WXModel
{
public static string access_token;
public static string AppID;
public static string AppSecret;
public static string mch_id;
public static string key;
}
public class HttpRequestUtil
{
#region 请求Url，不发送数据
/// <summary>
/// 请求Url，不发送数据
/// </summary>
public static string RequestUrl(string url)
{
return RequestUrl(url, "POST");
}
#endregion #region 请求Url，不发送数据
/// <summary>
/// 请求Url，不发送数据
/// </summary>
public static string RequestUrl(string url, string method)
{
// 设置参数
HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
CookieContainer cookieContainer = new CookieContainer();
request.CookieContainer = cookieContainer;
request.AllowAutoRedirect = true;
request.Method = method;
request.ContentType = "text/html";
request.Headers.Add("charset", "utf-8"); //发送请求并获取相应回应数据
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
//直到request.GetResponse()程序才开始向目标网页发送Post请求
Stream responseStream = response.GetResponseStream();
StreamReader sr = new StreamReader(responseStream, Encoding.Default);
//返回结果网页（html）代码
string content = sr.ReadToEnd();
return content;
}
#endregion #region 请求Url，发送json数据
/// <summary>
/// 请求Url，发送json数据
/// </summary>
public static string RequestUrlSendMsg(string url, string method,string JSONData)
{
byte[] bytes = Encoding.UTF8.GetBytes(JSONData);
// 设置参数
HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
CookieContainer cookieContainer = new CookieContainer();
request.CookieContainer = cookieContainer;
request.AllowAutoRedirect = true;
request.Method = method;
request.ContentType = "text/html";
request.Headers.Add("charset", "utf-8");
Stream reqstream = request.GetRequestStream();
reqstream.Write(bytes, 0, bytes.Length);
//声明一个HttpWebRequest请求
request.Timeout = 90000;
//设置连接超时时间
request.Headers.Set("Pragma", "no-cache");
//发送请求并获取相应回应数据
HttpWebResponse response = request.GetResponse() as HttpWebResponse;
//直到request.GetResponse()程序才开始向目标网页发送Post请求
Stream responseStream = response.GetResponseStream();
StreamReader sr = new StreamReader(responseStream, Encoding.Default);
//返回结果网页（html）代码
string content = sr.ReadToEnd();
return content;
}
#endregion
}