C# wx获取token基本方法

#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
var request = WebRequest.Create(url) as HttpWebRequest;
var 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
var 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();
var sr = new StreamReader(responseStream, Encoding.UTF8);
//返回结果网页（html）代码
string content = sr.ReadToEnd();

return content;
}

#endregion

 

#region 获取Json字符串某节点的值

/// <summary>
/// 获取Json字符串某节点的值
/// </summary>
public static string GetJsonValue(string jsonStr, string key)
{
string result = string.Empty;
if (!string.IsNullOrEmpty(jsonStr))
{
key = "\"" + key.Trim('"') + "\"";
int index = jsonStr.IndexOf(key) + key.Length + 1;
if (index > key.Length + 1)
{
//先截逗号，若是最后一个，截"｝"号，取最小值
int end = jsonStr.IndexOf(',', index);
if (end == -1)
{
end = jsonStr.IndexOf('}', index);
}
result = jsonStr.Substring(index, end - index);
result = result.Trim(new [] {'"', ' ', '\"'}); //过滤引号或空格
}
}
return result;
}

#endregion

#region 验证Token是否过期

/// <summary>
/// 验证Token是否过期
/// </summary>
public static bool TokenExpired(string access_token)
{
string jsonStr =
RequestUrl(string.Format("https://api.weixin.qq.com/cgi-bin/menu/get?access_token={0}",
access_token));
if (GetJsonValue(jsonStr, "errcode") == "42001")
{
return true;
}
return false;
}

#endregion

#region 获取Token

/// <summary>
/// 获取Token
/// </summary>
public static string GetToken(string appid, string secret)
{
string strJson =
RequestUrl(
string.Format(
"https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid={0}&secret={1}",
appid, secret));
return GetJsonValue(strJson, "access_token");
}

#endregion

//获取Openid

public static string GetOpenId(string appid, string secret, string code)
{
string strJson =
RequestUrl(
string.Format(
"https://api.weixin.qq.com/sns/jscode2session?appid={0}&secret={1}&js_code={2}&grant_type=authorization_code",
appid, secret, code));
//LogUtil.WriteLog(strJson);
return GetJsonValue(strJson, "openid");
}