RsCode.WeChat内封装多个常用的获取accesstoken的方法，自动处理accesstoken的有效期。

它定义于接口IWechatTokenManager中

//获取指定AppId的accessToken
Task<string> GetAccessTokenAsync(string appId);
//微信用户授权后获取到的token
Task<string> GetAccessTokenAsync( string appId,string code);
//第三方平台的componentAccessToken
Task<string> GetComponentTokenAsync(string componentAppId);
//第三方平台获取预授权码
Task<string> GetPreAuthCodeAsync(string componentAppId, string componentAccessToken);

注入IWeChatClient ,调用UseAppId("your appid")

public class Demo
{
    WeChatOptions WeChatOptions;
	IWeChatClient wechat;
	public Demo(IWeChatClient _wechat)
	{
	   wechat=_wechat;
	   WeChatOptions=wechat.UseAppId("your appid");
	}
	
	public async Task<object> GetAccessTokenAsync()
	{
	  //  cgi-bin/token
      await wechat.SendAsync<AppAccessTokenResponse>(new AppAccessTokenRequest(WeChatOptions.AppId,WeChatOptions.AppSecret));

      // sns/oauth2
      string code="";//用户授权的code
      await wechat.SendAsync<OAuthTokenResponse>(new OAuthTokenRequest(WeChatOptions.AppId,WeChatOptions.AppSecret,code));
	}
}

注意：该方法要缓存保存token

推荐：使用IWechatTokenManager ，它会将token自动缓存至内存中

public test(IWechatTokenManager _wechatTokenManager)
{
    wechatTokenManager = _wechatTokenManager;
}
public void GetToken()
{
    string appid="";
    //获取apptoken
    var token = await wechatTokenManager.GetAccessTokenAsync(appid); 
    //获取用户token
     var token = await wechatTokenManager.GetAccessTokenAsync(appid,code); 
}

定义类StoreHelper.cs,重新定义存储token的方法，例如

 public class StoreHelper : IStoreHelper
 {
     ICacheProvider cache;
     public StoreHelper(IEnumerable<ICacheProvider>caches)
     {
         cache = caches.FirstOrDefault(c => c.CacheName == "redis");
     }
     public T Get<T>(string key)
     {
         return cache.Get<T>(key);
     }

     public void Set(string key, object obj, int seconds = 7000)
     {
         cache.Set(key, obj, seconds);   
     }
 }

添加IStoreHelper到容器中

services.AddScoped<IStoreHelper,StoreHelper>();