SqlSugar/Src/Asp.NetCore2/DB2CoreTest/CURD/CodeFirst.cs

using SqlSugar;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DB2CoreTest.CURD
{
    public class CodeFirst
    {
        public static void Init()
        {
            // 获取新的数据库实例
            var db = DbHelper.GetNewDb();

            // 如果数据库不存在，则创建数据库
            //db.DbMaintenance.CreateDatabase();

            //实体类初始化表
            db.CodeFirst.InitTables<UserInfo>();

            //实体类初始化表
            db.CodeFirst.InitTables<UserLogins>();
        }

        public static void Insertable()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //插入用户
                var userId = db.Insertable(new UserInfo()
                {
                    Context = "Context",
                    Email = "dfafa@qq.com",
                    Price = Convert.ToDecimal(1.1),
                    UserName = "admin",
                    RegistrationDate = DateTime.Now,

                }).ExecuteReturnIdentity();

                //插入用户登录
                var loginId = db.Insertable(new UserLogins()
                {
                    LoginTime = DateTime.Now,
                    UserId = userId,

                }).ExecuteReturnIdentity();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Insertable发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void Queryable()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //查询用户
                var userInfo = db.Queryable<UserInfo>().ToList();

                //查询用户登录
                var userLogin = db.Queryable<UserLogins>().ToList();

                var user = userInfo.FirstOrDefault();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Queryable发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void QueryableSelect()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //查询用户
                var userInfo = db.Queryable<UserInfo>().First();

                //常量赋值
                var alias = "zhangsan";
                var isActived = false;
                var userInfoConst = db.Queryable<UserInfo>().Select(p => new Student { Name = p.UserName, Alias = alias, IsActived = isActived }).ToList();
                //对象赋值
                var userInfoObject = db.Queryable<UserInfo>().Select(p => new Student { Name = p.UserName, Alias = userInfo.UserName, IsActived = userInfo.IsActived }).ToList();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"QueryableSelect发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void JoinQuery()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                var queryResult = db.Queryable<UserInfo, UserLogins>((ui, ul) => new JoinQueryInfos(JoinType.Inner, ui.UserId == ul.UserId)).Select((ui, ul) => new
                {
                    ui.UserName,
                    ul.LoginTime,
                }).ToList();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"JoinQuery发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void PageQuery()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //查询用户
                var userList = db.Queryable<UserInfo>().ToPageList(2, 2);

                var queryResult = db.Queryable<UserInfo, UserLogins>((ui, ul) => new JoinQueryInfos(JoinType.Inner, ui.UserId == ul.UserId)).Select((ui, ul) => new
                {
                    ui.UserName,
                    ul.LoginTime,
                }).ToPageList(2, 2);
            }
            catch (Exception ex)
            {
                Console.WriteLine($"PageQuery发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void OrderBy()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //查询用户
                var userList = db.Queryable<UserInfo>().OrderBy(p => p.UserName).ToList();

                var queryResult = db.Queryable<UserInfo, UserLogins>((ui, ul) => new JoinQueryInfos(JoinType.Inner, ui.UserId == ul.UserId)).Select((ui, ul) => new
                {
                    ui.UserName,
                    ul.LoginTime,
                }).OrderBy(ui => ui.UserName).ToList();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"OrderBy发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void GroupBy()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //查询用户
                var userList = db.Queryable<UserInfo>().GroupBy(p => p.Email).Select(p => new { UserId = SqlFunc.AggregateMax(p.UserId), p.Email, }).OrderBy(p => p.UserId).ToList();

                var queryResult = db.Queryable<UserInfo, UserLogins>((ui, ul) => new JoinQueryInfos(JoinType.Inner, ui.UserId == ul.UserId)).GroupBy((ui, ul) =>
                new
                {
                    ui.UserName,
                })
                .Select((ui, ul) => new
                {
                    UserId = SqlFunc.AggregateMax(ui.UserId),
                    ui.UserName,
                    LoginTime = SqlFunc.AggregateMax(ul.LoginTime),
                }).OrderBy(ui => ui.UserName).ToList();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"GroupBy发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void Updateable()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //更新用户
                var ret = db.Updateable<UserInfo>(p => p.UserName == "test").Where(p => p.UserName == "admin").ExecuteCommand();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Updateable发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        public static void Deleteable()
        {
            try
            {
                // 获取新的数据库实例
                var db = DbHelper.GetNewDb();

                //查询用户
                var userList = db.Queryable<UserInfo>().ToList();
                //删除用户
                var deleteUserRet = db.Deleteable(userList).ExecuteCommand();

                //查询用户登录
                var userLoginList = db.Queryable<UserInfo>().ToList();
                //删除用户登录
                var deleteUserLoginRet = db.Deleteable(userLoginList).ExecuteCommand();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Deleteable发生异常，异常信息：{GetFullErrorMessage(ex)}");
            }
        }

        /// <summary>
        /// 获取完整的异常信息，包括堆栈信息
        /// </summary>
        /// <param name="ex">异常对象</param>
        /// <returns>返回完整异常信息</returns>
        private static string GetFullErrorMessage(Exception ex)
        {
            var message = new StringBuilder();
            message.AppendLine($"Message:{ex.Message}");
            message.AppendLine($"Type: {ex.GetType()}");
            message.AppendLine("StackTrace:");
            message.AppendLine(ex.StackTrace);
            if (ex.InnerException != null)
            {
                message.AppendLine("InnerException:");
                message.AppendLine(GetFullErrorMessage(ex.InnerException));
            }
            return message.ToString();
        }
    }

    /// <summary>
    /// 用户信息实体类
    /// </summary> 
    [SugarTable("USER_INFO", TableDescription = "用户信息")]
    public class UserInfo
    {
        /// <summary>
        /// 用户ID（主键）
        /// </summary>
        [SugarColumn(IsIdentity = true, IsPrimaryKey = true, ColumnDescription = "用户ID")]
        public int UserId { get; set; }

        /// <summary>
        /// 用户名
        /// </summary>
        [SugarColumn(Length = 50, IsNullable = false, ColumnDescription = "用户名")]
        public string UserName { get; set; }

        /// <summary>
        /// 用户邮箱
        /// </summary>
        [SugarColumn(IsNullable = true, ColumnDescription = "用户邮箱")]
        public string Email { get; set; }

        /// <summary>
        /// 产品价格
        /// </summary> 
        [SugarColumn(ColumnDescription = "产品价格")]
        public decimal Price { get; set; }

        /// <summary>
        /// 用户内容
        /// </summary>
        [SugarColumn(ColumnDataType = StaticConfig.CodeFirst_BigString, IsNullable = true, ColumnDescription = "用户内容")]
        public string Context { get; set; }

        /// <summary>
        /// 用户注册日期
        /// </summary>
        [SugarColumn(IsNullable = true, ColumnDescription = "用户注册日期")]
        public DateTime? RegistrationDate { get; set; }

        /// <summary>
        /// 是否启用
        /// </summary>
        [SugarColumn(ColumnDescription = "是否启用")]
        public bool IsActived { get; set; }
    }

    /// <summary>
    /// 用户登录实体类
    /// </summary> 
    [SugarTable("USER_LOGINS")]
    public class UserLogins
    {
        /// <summary>
        /// ID（主键）
        /// </summary>
        [SugarColumn(IsIdentity = true, IsPrimaryKey = true)]
        public int Id { get; set; }

        /// <summary>
        /// 用户ID
        /// </summary>
        [SugarColumn(IsNullable = false)]
        public int UserId { get; set; }

        /// <summary>
        /// 登录时间
        /// </summary>
        [SugarColumn(IsNullable = true)]
        public DateTime LoginTime { get; set; }
    }

    public class Student
    {
        /// <summary>
        /// 名称
        /// </summary>
        public string Name { get; set; }
        /// <summary>
        /// 别名
        /// </summary>
        public string Alias { get; set; }
        /// <summary>
        /// 启用
        /// </summary>
        public bool IsActived { get; set; }
    }
}