一个练习项目，好玩的bbs-c#

c#代码：

using MySql.Data.MySqlClient;
using System.Data;
using Newtonsoft.Json;
using System.Security.Cryptography;
using System.Text;

int pagesize = 20;
string secretKey = "saacac3423@21212";

var builder = WebApplication.CreateSlimBuilder(args);
var app = builder.Build();
app.UseHttpsRedirection();
app.Use((context, next) =>
{
    context.Response.Headers.Add("Server", "c#-webframework");
    return next(context);
});

app.MapGet("/", () => {
    string retstr = "此站接口使用c#实现，<a href='api.html' target='_blank'>接口列表</a>";

    return Results.Text(retstr);
});

app.MapGet("/user/register", (string username, string password, string nickname) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select id,username,nickname,addTime,sessionId from user where username='" + username + "'";
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    Dictionary<string, string> userinfo1 = new Dictionary<string, string>();
    if (reader.Read())
    {
        userinfo1.Add("id", reader.GetInt32("id").ToString());
        userinfo1.Add("username", reader.GetString("username"));
        userinfo1.Add("nickname", reader.GetString("nickname"));
        userinfo1.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
        userinfo1.Add("sessionId", reader.GetString("sessionId"));
    }
    reader.Close();

    RetinfoSp retinfo1 = new RetinfoSp();

    if (userinfo1.ContainsKey("id") && String.Compare(userinfo1["id"], "") != 0)
    {
        retinfo1.code = 1;
        retinfo1.msg = "用户名已经存在";
        retinfo1.data = "";
    }
    else
    {
        string passwordMd5 = string.Join("", MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(password)).Select(m => m.ToString("X2"))); 
        string sql2 = "insert into user(username, password, nickname) value('"+username+"', '"+ passwordMd5 + "', '"+nickname+"')";
        cmd = new MySqlCommand(sql2, conn);
        cmd.ExecuteNonQuery();

        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = cmd.LastInsertedId.ToString();
    }

    conn.Clone();

    string json = JsonConvert.SerializeObject(retinfo1);

    return Results.Text(json);
});

app.MapGet("/user/login", (string username, string password) => {
    string passwordMd5 = string.Join("", MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(password)).Select(m => m.ToString("X2")));
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select id,username,nickname,addTime,sessionId from user where username='" + username + "' and password='"+ passwordMd5 + "'";
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    Dictionary<string, string> userinfo1 = new Dictionary<string, string>();
    if (reader.Read())
    {
        userinfo1.Add("id", reader.GetInt32("id").ToString());
        userinfo1.Add("username", reader.GetString("username"));
        userinfo1.Add("nickname", reader.GetString("nickname"));
        userinfo1.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
        userinfo1.Add("sessionId", reader.GetString("sessionId"));
    }
    reader.Close();

    Retinfo retinfo1 = new Retinfo();

    if (!userinfo1.ContainsKey("id") || String.Compare(userinfo1["id"], "") == 0)
    {
        retinfo1.code = 1;
        retinfo1.msg = "用户名或者密码错误";
        retinfo1.data = userinfo1;
    }
    else
    {
        string tmpSessionId = string.Join("", MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(secretKey + userinfo1["id"] + userinfo1["addTime"])).Select(m => m.ToString("X2")));
        string sql2 = "update user set sessionId='" + tmpSessionId + "' where id='" + userinfo1["id"] + "'";
        cmd = new MySqlCommand(sql2, conn);
        cmd.ExecuteNonQuery();
        userinfo1["sessionId"] = tmpSessionId;

        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = userinfo1;
    }

    conn.Clone();

    string json = JsonConvert.SerializeObject(retinfo1);

    return Results.Text(json);
});

app.MapGet("/user/logout", (string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select id,username,nickname,addTime,sessionId from user where sessionId='" + sessionId + "'";
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    Dictionary<string, string> userinfo1 = new Dictionary<string, string>();
    if (reader.Read())
    {
        userinfo1.Add("id", reader.GetInt32("id").ToString());
        userinfo1.Add("username", reader.GetString("username"));
        userinfo1.Add("nickname", reader.GetString("nickname"));
        userinfo1.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
        userinfo1.Add("sessionId", reader.GetString("sessionId"));
    }
    reader.Close();

    string sql2 = "update user set sessionId='' where sessionId='" + sessionId + "'";
    cmd = new MySqlCommand(sql2, conn);
    cmd.ExecuteNonQuery();

    Retinfo retinfo1 = new Retinfo();
    retinfo1.code = 0;
    retinfo1.msg = "";
    retinfo1.data = userinfo1;

    conn.Clone();

    string json = JsonConvert.SerializeObject(retinfo1);

    return Results.Text(json);
});

app.MapGet("/user/getuserinfo", (string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select id,username,nickname,addTime,sessionId from user where sessionId='" + sessionId + "'";
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    Dictionary<string, string> userinfo1 = new Dictionary<string, string>();
    if (reader.Read()){
        userinfo1.Add("id", reader.GetInt32("id").ToString());
        userinfo1.Add("username", reader.GetString("username"));
        userinfo1.Add("nickname", reader.GetString("nickname"));
        userinfo1.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
        userinfo1.Add("sessionId", reader.GetString("sessionId"));
    }
    reader.Close();

    Retinfo retinfo1 = new Retinfo();
    retinfo1.code = 0;
    retinfo1.msg = "";
    retinfo1.data = userinfo1;

    conn.Clone();

    string json = JsonConvert.SerializeObject(retinfo1);

    return Results.Text(json);
});

app.MapGet("/post/list", (string keyword = "", int page = 1) => {
    if (page <= 0)
    {
        page = 1;
    }

    int start = (page - 1) * pagesize;

    string addsql = " isDel=0 ";
    if (String.Compare(keyword, "") != 0)
    {
        addsql = " isDel=0 and title like '%" + keyword + "%' ";
    }

    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select count(1) as count from content where " + addsql;
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    int count = 0;
    if (reader.Read())
    {
        count = reader.GetInt32("count");
    }
    reader.Close();

    int totalpage = Convert.ToInt32(Math.Ceiling((double)count / (double)pagesize));

    string sql2 = "select id,title,userId,userNickename,replyNum,updateTime from content where " + addsql + " order by updateTime desc limit " + start + "," + pagesize;
    cmd = new MySqlCommand(sql2, conn);
    reader = cmd.ExecuteReader();

    List<Dictionary<string, string>> postlist = new List<Dictionary<string, string>>();
    while (reader.Read())
    {
        Dictionary<string, string> postitem = new Dictionary<string, string>();
        postitem.Add("id", reader.GetInt32("id").ToString());
        postitem.Add("title", reader.GetString("title"));
        postitem.Add("userId", reader.GetInt32("userId").ToString());
        postitem.Add("userNickename", reader.GetString("userNickename"));
        postitem.Add("replyNum", reader.GetInt32("replyNum").ToString());
        postitem.Add("updateTime", reader.GetDateTime("updateTime").ToString("yyyy-MM-dd HH:mm:ss"));
        postlist.Add(postitem);
    }
    reader.Close();

    Listdata listdata1 = new Listdata();
    listdata1.totalpage = totalpage;
    listdata1.data = postlist;

    Retlist retlist1 = new Retlist();
    retlist1.code = 0;
    retlist1.msg = "";
    retlist1.data = listdata1;

    conn.Clone();

    string json = JsonConvert.SerializeObject(retlist1);

    return Results.Text(json);
});

app.MapGet("/post/detail", (int id) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select id,title,content,userId,userNickename,replyNum,updateTime from content where isDel=0 and id="+ id.ToString();
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    Dictionary<string, string> postinfo1 = new Dictionary<string, string>();
    if (reader.Read())
    {
        postinfo1.Add("id", reader.GetInt32("id").ToString());
        postinfo1.Add("title", reader.GetString("title"));
        postinfo1.Add("content", reader.GetString("content"));
        postinfo1.Add("userId", reader.GetInt32("userId").ToString());
        postinfo1.Add("userNickename", reader.GetString("userNickename"));
        postinfo1.Add("replyNum", reader.GetInt32("replyNum").ToString());
        postinfo1.Add("updateTime", reader.GetDateTime("updateTime").ToString("yyyy-MM-dd HH:mm:ss"));
    }
    reader.Close();

    Retinfo retinfo1 = new Retinfo();
    retinfo1.code = 0;
    retinfo1.msg = "";
    retinfo1.data = postinfo1;

    conn.Clone();

    string json = JsonConvert.SerializeObject(retinfo1);

    return Results.Text(json);
});

app.MapGet("/post/add", (string title, string content, string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    Userinfo userinfo1 = new Userinfo();
    Dictionary<string, string> userinfo2 = userinfo1.getloginuserinfo(sessionId);
    RetinfoSp retinfo1 = new RetinfoSp();
    string json = "";

    if (!userinfo2.ContainsKey("id") || String.Compare(userinfo2["id"], "") == 0)
    {
        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "请先登录";
        json = JsonConvert.SerializeObject(retinfo1);
    }
    else
    {
        string sql1 = "insert into content(title, content, userId, userNickename) value('" + title + "', '" + content + "', " + userinfo2["id"] + ", '" + userinfo2["nickname"] + "')";
        cmd = new MySqlCommand(sql1, conn);
        cmd.ExecuteNonQuery();

        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = cmd.LastInsertedId.ToString();
        json = JsonConvert.SerializeObject(retinfo1);
    }

    conn.Clone();

    return Results.Text(json);
});

app.MapGet("/post/edit", (int id, string title, string content, string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    Userinfo userinfo1 = new Userinfo();
    Dictionary<string, string> userinfo2 = userinfo1.getloginuserinfo(sessionId);
    RetinfoSp retinfo1 = new RetinfoSp();
    string json = "";

    if (!userinfo2.ContainsKey("id") || String.Compare(userinfo2["id"], "") == 0)
    {
        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "请先登录";
        json = JsonConvert.SerializeObject(retinfo1);
    }
    else
    {
        string sql1 = "update content set title='"+title+"',content='"+content+"',userId="+ userinfo2["id"].ToString() + ",userNickename='"+ userinfo2["nickname"] + "' where id="+ id.ToString()+ " and userId="+ userinfo2["id"].ToString();
        cmd = new MySqlCommand(sql1, conn);
        cmd.ExecuteNonQuery();

        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "";
        json = JsonConvert.SerializeObject(retinfo1);
    }

    conn.Clone();

    return Results.Text(json);
});

app.MapGet("/post/delete", (int id, string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    Userinfo userinfo1 = new Userinfo();
    Dictionary<string, string> userinfo2 = userinfo1.getloginuserinfo(sessionId);
    RetinfoSp retinfo1 = new RetinfoSp();
    string json = "";

    if (!userinfo2.ContainsKey("id") || String.Compare(userinfo2["id"], "") == 0)
    {
        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "请先登录";
        json = JsonConvert.SerializeObject(retinfo1);
    }
    else
    {
        string sql1 = "update content set isDel=1 where id=" + id.ToString() + " and userId=" + userinfo2["id"].ToString();
        cmd = new MySqlCommand(sql1, conn);
        cmd.ExecuteNonQuery();

        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "";
        json = JsonConvert.SerializeObject(retinfo1);
    }

    conn.Clone();

    return Results.Text(json);
});

app.MapGet("/reply/list", (int contentId = 0, int page = 1) => {
    if (page <= 0)
    {
        page = 1;
    }

    int start = (page - 1) * pagesize;

    string addsql = " isDel=0 and contentId="+ contentId.ToString() + " ";

    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select count(1) as count from reply where " + addsql;
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    int count = 0;
    if (reader.Read())
    {
        count = reader.GetInt32("count");
    }
    reader.Close();

    int totalpage = Convert.ToInt32(Math.Ceiling((double)count / (double)pagesize));

    string sql2 = "select id,content,replyUserId,replyUserNickename,addTime from reply where " + addsql + " order by id asc limit " + start + "," + pagesize;
    cmd = new MySqlCommand(sql2, conn);
    reader = cmd.ExecuteReader();

    List<Dictionary<string, string>> postlist = new List<Dictionary<string, string>>();
    while (reader.Read())
    {
        Dictionary<string, string> postitem = new Dictionary<string, string>();
        postitem.Add("id", reader.GetInt32("id").ToString());
        postitem.Add("content", reader.GetString("content"));
        postitem.Add("replyUserId", reader.GetInt32("replyUserId").ToString());
        postitem.Add("replyUserNickename", reader.GetString("replyUserNickename"));
        postitem.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
        postlist.Add(postitem);
    }
    reader.Close();

    Listdata listdata1 = new Listdata();
    listdata1.totalpage = totalpage;
    listdata1.data = postlist;

    Retlist retlist1 = new Retlist();
    retlist1.code = 0;
    retlist1.msg = "";
    retlist1.data = listdata1;

    conn.Clone();

    string json = JsonConvert.SerializeObject(retlist1);

    return Results.Text(json);
});

app.MapGet("/reply/detail", (int id) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    string sql1 = "select id,content,replyUserId,replyUserNickename,addTime from reply where isDel=0 and id=" + id.ToString();
    cmd = new MySqlCommand(sql1, conn);
    reader = cmd.ExecuteReader();

    Dictionary<string, string> postinfo1 = new Dictionary<string, string>();
    if (reader.Read())
    {
        postinfo1.Add("id", reader.GetInt32("id").ToString());
        postinfo1.Add("content", reader.GetString("content"));
        postinfo1.Add("replyUserId", reader.GetInt32("replyUserId").ToString());
        postinfo1.Add("replyUserNickename", reader.GetString("replyUserNickename"));
        postinfo1.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
    }
    reader.Close();

    Retinfo retinfo1 = new Retinfo();
    retinfo1.code = 0;
    retinfo1.msg = "";
    retinfo1.data = postinfo1;

    conn.Clone();

    string json = JsonConvert.SerializeObject(retinfo1);

    return Results.Text(json);
});

app.MapGet("/reply/add", (int contentId, string content, string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    Userinfo userinfo1 = new Userinfo();
    Dictionary<string, string> userinfo2 = userinfo1.getloginuserinfo(sessionId);
    RetinfoSp retinfo1 = new RetinfoSp();
    string json = "";

    if (!userinfo2.ContainsKey("id") || String.Compare(userinfo2["id"], "") == 0)
    {
        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "请先登录";
        json = JsonConvert.SerializeObject(retinfo1);
    }
    else
    {
        string sql2 = "update content set replyNum=replyNum+1 where id="+contentId.ToString();
        cmd = new MySqlCommand(sql2, conn);
        cmd.ExecuteNonQuery();

        string sql1 = "insert into reply(contentId, content, replyUserId, replyUserNickename) value("+ contentId.ToString() + ", '"+ content + "', "+ userinfo2["id"] + ", '"+ userinfo2["nickname"] + "')";
        cmd = new MySqlCommand(sql1, conn);
        cmd.ExecuteNonQuery();

        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = cmd.LastInsertedId.ToString();
        json = JsonConvert.SerializeObject(retinfo1);
    }

    conn.Clone();

    return Results.Text(json);
});

app.MapGet("/reply/edit", (int id, string content, string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    Userinfo userinfo1 = new Userinfo();
    Dictionary<string, string> userinfo2 = userinfo1.getloginuserinfo(sessionId);
    RetinfoSp retinfo1 = new RetinfoSp();
    string json = "";

    if (!userinfo2.ContainsKey("id") || String.Compare(userinfo2["id"], "") == 0)
    {
        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "请先登录";
        json = JsonConvert.SerializeObject(retinfo1);
    }
    else
    {
        string sql1 = "update reply set content='"+ content + "',replyUserId="+ userinfo2["id"] + ",replyUserNickename='"+ userinfo2["nickname"] + "' where id="+id.ToString()+" and replyUserId=" + userinfo2["id"];
        cmd = new MySqlCommand(sql1, conn);
        cmd.ExecuteNonQuery();

        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "";
        json = JsonConvert.SerializeObject(retinfo1);
    }

    conn.Clone();

    return Results.Text(json);
});

app.MapGet("/reply/delete", (int id, string sessionId) => {
    string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
    MySqlConnection conn = new MySqlConnection(mysqlcon);
    conn.Open();
    MySqlCommand cmd;
    MySqlDataReader reader;

    Userinfo userinfo1 = new Userinfo();
    Dictionary<string, string> userinfo2 = userinfo1.getloginuserinfo(sessionId);
    RetinfoSp retinfo1 = new RetinfoSp();
    string json = "";

    if (!userinfo2.ContainsKey("id") || String.Compare(userinfo2["id"], "") == 0)
    {
        retinfo1.code = 0;
        retinfo1.msg = "";
        retinfo1.data = "请先登录";
        json = JsonConvert.SerializeObject(retinfo1);
    }
    else
    {
        string sql3 = "select id,content,replyUserId,replyUserNickename,addTime,contentId from reply where isDel=0 and id=" + id.ToString();
        cmd = new MySqlCommand(sql3, conn);
        reader = cmd.ExecuteReader();

        Dictionary<string, string> postinfo1 = new Dictionary<string, string>();
        if (reader.Read())
        {
            postinfo1.Add("id", reader.GetInt32("id").ToString());
            postinfo1.Add("content", reader.GetString("content"));
            postinfo1.Add("replyUserId", reader.GetInt32("replyUserId").ToString());
            postinfo1.Add("replyUserNickename", reader.GetString("replyUserNickename"));
            postinfo1.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
            postinfo1.Add("contentId", reader.GetInt32("contentId").ToString());
        }
        reader.Close();

        if (postinfo1.ContainsKey("id") && String.Compare(postinfo1["id"], "") != 0)
        {
            string sql2 = "update content set replyNum=replyNum-1 where id=" + postinfo1["contentId"];
            cmd = new MySqlCommand(sql2, conn);
            cmd.ExecuteNonQuery();

            string sql1 = "update reply set isDel=1 where id=" + id.ToString() + " and replyUserId=" + userinfo2["id"];
            cmd = new MySqlCommand(sql1, conn);
            cmd.ExecuteNonQuery();

            retinfo1.code = 0;
            retinfo1.msg = "";
            retinfo1.data = "";
            json = JsonConvert.SerializeObject(retinfo1);
        }
        else {
            retinfo1.code = 0;
            retinfo1.msg = "";
            retinfo1.data = "回复不存在";
            json = JsonConvert.SerializeObject(retinfo1);
        }
    }

    conn.Clone();

    return Results.Text(json);
});

app.Urls.Add("http://localhost:2086");
app.Urls.Add("http://localhost:1086");
app.Run();

public struct Listdata
{
    public int totalpage;
    public List<Dictionary<string, string>> data;
};

public struct Retlist
{
    public int code;
    public string msg;
    public Listdata data;
};

public struct Retinfo
{
    public int code;
    public string msg;
    public Dictionary<string, string> data;
};

public struct RetinfoSp
{
    public int code;
    public string msg;
    public string data;
};

class Userinfo {
    public Dictionary<string, string> getloginuserinfo(string sessionId) {
        string mysqlcon = "server=127.0.0.1;database=my_bbs;user=root;password=123456";
        MySqlConnection conn = new MySqlConnection(mysqlcon);
        conn.Open();
        MySqlCommand cmd;
        MySqlDataReader reader;

        string sql1 = "select id,username,nickname,addTime,sessionId from user where sessionId='" + sessionId + "'";
        cmd = new MySqlCommand(sql1, conn);
        reader = cmd.ExecuteReader();

        Dictionary<string, string> userinfo1 = new Dictionary<string, string>();
        if (reader.Read())
        {
            userinfo1.Add("id", reader.GetInt32("id").ToString());
            userinfo1.Add("username", reader.GetString("username"));
            userinfo1.Add("nickname", reader.GetString("nickname"));
            userinfo1.Add("addTime", reader.GetDateTime("addTime").ToString("yyyy-MM-dd HH:mm:ss"));
            userinfo1.Add("sessionId", reader.GetString("sessionId"));
        }
        reader.Close();

        return userinfo1;
    }
}

 

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