# 删除数据 | 方法 | 返回值 | 参数 | 描述 | | - | - | - | - | | Where | \ | Lambda | 表达式条件,仅支持实体基础成员(不包含导航对象) | | Where | \ | string, parms | 原生sql语法条件,Where("id = ?id", new { id = 1 }) | | Where | \ | T1 \| IEnumerable | 传入实体或集合,将其主键作为条件 | | WhereExists | \ | ISelect | 子查询是否存在 | | ToSql | string | | 返回即将执行的SQL语句 | | ExecuteAffrows | long | | 执行SQL语句,返回影响的行数 | | ExecuteDeleted | List\ | | 执行SQL语句,返回被删除的记录 | ### 测试代码 ```csharp IFreeSql fsql = new FreeSql.FreeSqlBuilder() .UseConnectionString(FreeSql.DataType.MySql, "Data Source=127.0.0.1;Port=3306;User ID=root;Password=root;Initial Catalog=cccddd;Charset=utf8;SslMode=none;Max pool size=10") .Build(); IDelete delete => fsql.Delete(); [Table(Name = "tb_topic")] class Topic { [Column(IsIdentity = true, IsPrimary = true)] public int Id { get; set; } public int Clicks { get; set; } public TestTypeInfo Type { get; set; } public string Title { get; set; } public DateTime CreateTime { get; set; } } ``` ### 动态条件 ```csharp Delete(object dywhere) ``` dywhere 支持 * 主键值 * new[] { 主键值1, 主键值2 } * Topic对象 * new[] { Topic对象1, Topic对象2 } * new { id = 1 } ```csharp var t1 = fsql.Delete(new[] { 1, 2 }).ToSql(); //DELETE FROM `tb_topic` WHERE (`Id` = 1 OR `Id` = 2) var t2 = fsql.Delete(new Topic { Id = 1, Title = "test" }).ToSql(); //DELETE FROM `tb_topic` WHERE (`Id` = 1) var t3 = fsql.Delete(new[] { new Topic { Id = 1, Title = "test" }, new Topic { Id = 2, Title = "test" } }).ToSql(); //DELETE FROM `tb_topic` WHERE (`Id` = 1 OR `Id` = 2) var t4 = fsql.Delete(new { id = 1 }).ToSql(); //DELETE FROM `tb_topic` WHERE (`Id` = 1) ``` ### 删除条件 ```csharp var t5 = delete.Where(a => a.Id == 1).ToSql().Replace("\r\n", ""); //DELETE FROM `tb_topic` WHERE (`Id` = 1) var t6 = delete.Where("id = ?id", new { id = 1 }).ToSql().Replace("\r\n", ""); //DELETE FROM `tb_topic` WHERE (id = ?id) var item = new Topic { Id = 1, Title = "newtitle" }; var t7 = delete.Where(item).ToSql().Replace("\r\n", ""); //DELETE FROM `tb_topic` WHERE (`Id` = 1) var items = new List(); for (var a = 0; a < 10; a++) items.Add(new Topic { Id = a + 1, Title = $"newtitle{a}", Clicks = a * 100 }); var t8 = delete.Where(items).ToSql().Replace("\r\n", ""); //DELETE FROM `tb_topic` WHERE (`Id` IN (1,2,3,4,5,6,7,8,9,10)) ``` ### 执行命令 | 方法 | 返回值 | 参数 | 描述 | | - | - | - | - | | ExecuteAffrows | long | | 执行SQL语句,返回影响的行数 | | ExecuteDeleted | List\ | | 执行SQL语句,返回被删除的记录 |