c#自定义ORM框架-实体类扩展属性

步骤一、建立扩展属性类

实体类扩展属性要继承Attribute基类完成

步骤二、创建实体类并引用扩展实体类属性

Attributes属性定义，主要标明表名和主键名字

/// <summary>
///  表名
/// </summary>
[AttributeUsage(AttributeTargets.Class)]
[System.Serializable]
public class TableNameAttribute : Attribute
{public object _value { get; private set; }public TableNameAttribute(string tableName){this._value = tableName;}
}/// <summary>
/// 主键名
/// </summary>
[AttributeUsage(AttributeTargets.Class)]
[System.Serializable]
public class PrimaryKeyAttribute : Attribute
{public object _value { get; private set; }public PrimaryKeyAttribute(string primaryKey){this._value = primaryKey;}
}// 使用方式（例）/// <summary>/// 学生类/// </summary>[TableName("MapRecord")][PrimaryKey("ID")]public class Student{// 身份IDpublic int Id { get; set; }// 名字public string Name { get; set; }// 长度public long Length { get; set; }}

 1 [AttributeUsage(AttributeTargets.Property)]2     public class FieldAttribute : Attribute3     {4         /// <summary>5         ///是否为主键（true/false）6         /// </summary>7         public bool PropertyKey { get; set; }8         /// <summary>9         /// 是否为自动增长（true/false）
10         /// </summary>
11         public bool Identity { get; set; }
12     }

1 [AttributeUsage(AttributeTargets.Class)]
2     public class TableAttribute:Attribute
3     {
4         /// <summary>
5         /// 数据库表名
6         /// </summary>
7         public string TableName { get; set; }
8     }

 [Table(TableName = "emesc.Dome")]2     [Serializable]3     public class Dome4     {5         [Field(PropertyKey = true)]6         public string EMP_NO { get; set; }7         public string EMP_NAME { get; set; }8         public string EMP_DESC { get; set; }9         public string TYPE { get; set; }
10         public string EMP_RANK { get; set; }
11         public string EMP_PASS { get; set; }
12         public object FACTORY_CODE { get; set; }
13         public DateTime QUIT_DATE { get; set; }
14         public object CALENDAR_CODE { get; set; }
15     }

/// <summary>/// 主键特性（在实体类的上方加这个特性，指定该类的主键名称）/// </summary>[AttributeUsage(AttributeTargets.Class)]public class PrimaryKeyAttribute : Attribute{private PrimaryKeyAttribute(){}private string _name;/// <summary>/// 构造方法/// </summary>/// <param name="name"></param>public PrimaryKeyAttribute(string name){_name = name;}/// <summary>/// 主键名称/// </summary>public string Name{get { return _name; }}}