SqlSugarClient 代码优先建表， 根据给定的实体类，创建SQL语句, 之后创建MySQL表

using SqlSugar;
using System;
using System.Collections.Generic;
using System.Reflection;
using System.Text;namespace DDD
{/// <summary>/// /// SqlSugarClient 代码优先建表/// 根据给定的实体类，创建SQL语句, 之后创建MySQL表/// /// 优势：///     随便给一个C# 实体类，就可以建表。///     无需给实体类的属性添加额外的属性。如：繁琐的 [SugarColumn(IsPrimaryKey =true)]等。/// /// 用法：///     CreateMySQLTableCodeFirst.CreateTablesBySQL(DB, typeof(YourType1),typeof(YourType2));///    /// 后续做法：///     如果对字段的类型不满意，可以用 HeidiSQL 软件修改表的字段和类型///     添加字段、修改字段名称、添加索引，也用该软件。///    /// by lmp 2024.11.15/// /// </summary>public class CreateTableCodeFirstOnMySQL{/// <summary>/// 创建表/// </summary>/// <param name="db"></param>/// <param name="entityTypes"></param>public static void CreateTablesBySQL(SqlSugarClient db, params Type[] entityTypes){foreach (Type entityType in entityTypes){string sql = GetCreateTableSQLOfType(entityType);db.Ado.ExecuteCommand(sql);Log.Msg($"创建表完成 【{entityType.Name}】");}}/// <summary>/// 生成建表SQL语句/// </summary>/// <param name="entityType"></param>/// <returns></returns>public static string GetCreateTableSQLOfType(Type entityType){string tableName = entityType.Name;string sqlPropertys = CreateOther(entityType);StringBuilder sb = new StringBuilder();sb.Append($@"
CREATE TABLE `{tableName}` (`Id` BIGINT NOT NULL AUTO_INCREMENT,{sqlPropertys},PRIMARY KEY (`Id`) USING BTREE
)
COLLATE='utf8mb4_0900_ai_ci'
ENGINE=InnoDB
");return sb.ToString();}/// <summary>/// 创建除了Id 以外的其他类型/// </summary>/// <param name="entityType"></param>/// <returns></returns>/// <exception cref="Exception"></exception>private static string CreateOther(Type entityType){PropertyInfo[] piArray = entityType.GetProperties();  // 类型T的所有公共属性
List<string> items = new List<string>();foreach (PropertyInfo pi in piArray){string columnName = pi.Name;if (columnName.ToUpper() == "ID")  // 排除Id ,因为已经创建了语句
                {continue;}Type tp = pi.PropertyType;if (tp == typeof(DateTime) || tp == typeof(DateTime?)){items.Add($"`{columnName}` DATETIME NULL ");}else if (tp == typeof(float) || tp == typeof(float?)){items.Add($"`{columnName}` DOUBLE NULL DEFAULT 0 ");}else if (tp == typeof(double) || tp == typeof(double?)){items.Add($"`{columnName}` DOUBLE NULL DEFAULT 0 ");}else if (tp == typeof(decimal) || tp == typeof(decimal?)){items.Add($"`{columnName}` DOUBLE NULL DEFAULT 0 ");}else if (tp == typeof(int) || tp == typeof(int?)){items.Add($"`{columnName}` INT NULL DEFAULT 0 ");}else if (tp == typeof(long) || tp == typeof(long?)){items.Add($"`{columnName}` BIGINT NULL DEFAULT 0 ");}else if (tp == typeof(bool) || tp == typeof(bool?)){items.Add($"`{columnName}` TINYINT(1) NULL DEFAULT 0 ");}else if (tp == typeof(string)){items.Add($"`{columnName}` VARCHAR(255) NULL DEFAULT NULL  ");}else if (tp == typeof(byte[])){items.Add($"`{columnName}` LONGBLOB NULL DEFAULT NULL ");}else{throw new Exception($"{entityType.Name} 中{columnName}的未知类型：" + tp);}}return string.Join(", \r\n", items);}}
}