C#获取用户基本信息一（关注了公众号的用户）

一、获取Code

假设我们需要网页授权的页面的地址为redirect_uri

需要获取Code的话我们第一步是跳转到授权地址，我们第一步便是获取拼接授权地址 --采用snsapi_base方式

public partial class WebAuth : System.Web.UI.Page
{
string Appid = "XXXXXXXXXXXXXXXXXX";
string redirect_uri = "http://www.xxxxx.com/wx/GetUserInfor.aspx";
protected void Page_Load(object sender, EventArgs e)
{

string url = GetCodeUrl(Appid, redirect_uri);
Response.Redirect(url);
}

/// <summary>
/// 对页面是否要用授权 用snsapi_base方式 获取Code Appid是微信应用id
/// </summary>
/// <returns></returns>
public string GetCodeUrl(string Appid, string redirect_uri)
{
return string.Format("https://open.weixin.qq.com/connect/oauth2/authorize?appid={0}&redirect_uri={1}&response_type=code&scope=snsapi_base&state=STATE#wechat_redirect", Appid, redirect_uri);
}

}

当在微信中打开如下地址的时候如果授权成功，会自动跳转到页面redirect_uri?code=CODE&state=STATE，这样我们就可以获取到Code了

二、用Code换取Openid、再用Openid获取用户的基本信息

用get方法获取到json格式的数据，

{
"access_token":"ACCESS_TOKEN",
"expires_in":7200,
"refresh_token":"REFRESH_TOKEN",
"openid":"OPENID",
"scope":"SCOPE",
"unionid": "o6_bmasdasdsad6_2sgVt7hMZOPfL"
}

public partial class GetUserInfor : System.Web.UI.Page
{
string Appid = "wxceefad22b094e8a9";
string Appsecret = "935c3d938aa26fa4f627b4926afd4b16";
protected void Page_Load(object sender, EventArgs e)
{
string code = Request["code"];
string openid = CodeGetOpenid(code);
Dictionary<string, object> userInfor = GetUserInfo(openid);
Response.Write(userInfor["nickname"]);
}

/// <summary>
/// 用Code换取Openid
/// </summary>
/// <param name="Code"></param>
/// <returns></returns>
public string CodeGetOpenid(string Code)
{
string url = string.Format("https://api.weixin.qq.com/sns/oauth2/access_token?appid={0}&secret={1}&code={2}&grant_type=authorization_code", Appid, Appsecret, Code);
string ReText = WebRequestHelper.WebRequestPostOrGet(url, "");//post/get方法获取信息

JavaScriptSerializer Jss = new JavaScriptSerializer();
Dictionary<string, object> DicText = (Dictionary<string, object>)Jss.DeserializeObject(ReText);
if (!DicText.ContainsKey("openid"))
return "";
return DicText["openid"].ToString();
}

/// <summary>
/// 用openid换取用户信息
/// </summary>
/// <param name="openid">微信标识id</param>
/// <returns></returns>
public Dictionary<string, object> GetUserInfo(string openid)
{
JavaScriptSerializer Jss = new JavaScriptSerializer();
string access_token = AccessToken.GetAccessToken();//获取access_token
string url = string.Format("https://api.weixin.qq.com/cgi-bin/user/info?access_token={0}&openid={1}&lang=zh_CN", access_token, openid);
Dictionary<string, object> respDic = (Dictionary<string, object>)Jss.DeserializeObject(WebRequestHelper.WebRequestPostOrGet(url, ""));
return respDic;

//{"subscribe":1,"openid":"oOPoPs_d7K8mVLX6--WPMSbaNl5o","nickname":"SKY","sex":1,"language":"zh_CN","city":"武汉","province":"湖北","country":"中国","headimgurl":"http:\/\/wx.qlogo.cn\/mmopen\/icayX4JkqCu1d3esVCQ8rSfXlgibQLKaD3z73qhbPln3ZhMh5oNw5243vpoVZFXDKMhTqxQ76OzY934nlm3iaulq60058VmEV5v\/0","subscribe_time":1495188935,"remark":"","groupid":0,"tagid_list":[]}

}
}

WebRequestHelper.WebRequestPostOrGet 方法如下：

public class WebRequestHelper
{
public static string WebRequestPostOrGet(string posturl, string postData)
{
Stream outstream = null;
Stream instream = null;
StreamReader sr = null;
HttpWebResponse response = null;
HttpWebRequest request = null;
Encoding encoding = Encoding.UTF8;

byte[] data = encoding.GetBytes(postData);
// 准备请求...
try
{
// 设置参数
request = WebRequest.Create(posturl) as HttpWebRequest;
CookieContainer cookieContainer = new CookieContainer();
request.CookieContainer = cookieContainer;
request.AllowAutoRedirect = true;
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = data.Length;
outstream = request.GetRequestStream();
outstream.Write(data, 0, data.Length);
outstream.Close();
//发送请求并获取相应回应数据
response = request.GetResponse() as HttpWebResponse;
//直到request.GetResponse()程序才开始向目标网页发送Post请求
instream = response.GetResponseStream();
sr = new StreamReader(instream, encoding);
//返回结果网页（html）代码
string content = sr.ReadToEnd();
return content;
}
catch (Exception ex)
{
string err = ex.Message;
return string.Format("{\"errcode\":-2,\"errmsg\":\"{0}\"}", err);
}
}
}

说明：以上代码本人也是在网上搜索根本别人的代码综合参考改写而来。

如需要获取“未关注公众号的用户信息”，这个本人项目中还没有遇到，仅提供参考链接：http://www.cnblogs.com/net-xiejun/p/4632711.html