[游戏开发]SqlSugar 2.实体配置

1.实体使用自带特性

对于CURD来说，只需要配置主键和自增列就行；类的名称和数据库表名不同时，也可设置

1.1 主键自增

[SugarTable("dbstudent")]//当和数据库名称不一样可以设置表别名 指定表明
public class Student
{
    [SugarColumn(IsPrimaryKey = true, IsIdentity = true)]//数据库是自增才配自增 
    public int Id { get; set; }

    public int? SchoolId { get; set; }

    [SugarColumn(ColumnName = "StudentName")]//数据库与实体不一样设置列名 
    public string Name { get; set; }
}

//创建表语句
db.CodeFirst.SetStringDefaultLength(200).InitTables(typeof(Student));

1.2 双主键、复合主键、联合主键、多个主键

public?class?Student
{
????[SugarColumn(IsPrimaryKey?=?true)]?//设置主键
????public?Guid??Pk1{?get;?set;?}
????[SugarColumn(IsPrimaryKey?=?true)]?//设置主键
????public?Guid??Pk2{?get;?set;?}
????public?string?Name?{?get;?set;?}
}

1.3 无主键

public?class?Student
{
????public?Guid??Id{?get;?set;?}
????public?string?Name?{?get;?set;?}
}

2.实体使用自定义特性

2.1 创建特性的类

    /// <summary>
??? /// 给类添加的特性
??? /// </summary>
??? [AttributeUsage(AttributeTargets.Class, Inherited = true)]
??? public class SugarTest1 : Attribute
??? {
??????? public SugarTest1()
??????? {}
??????? public string TestTableName { get; set; }

??????? public SugarTest1(string name)
??????? {
??????????? this.TestTableName = name;
??????? }
??? }


??? /// <summary>
??? /// 给属性添加的特性
??? /// </summary>
??? [AttributeUsage(AttributeTargets.Property, Inherited = true)]
??? public class SugarTest2 : Attribute
??? {
??????? private string _ColumnName1;
??????? public string ColumnName1
??????? {
??????????? get { return _ColumnName1; }
??????????? set { _ColumnName1 = value; }
??????? }
        
??????? private bool _IsIgnore1;
??????? public bool IsIgnore1
??????? {
??????????? get { return _IsIgnore1; }
??????????? set { _IsIgnore1 = value; }
??????? }
??? }

2.2 创建带自定义特性的实体类

?   [SugarTest1("TestClass")]
??? public class Test
??? {
??????? [SugarTest2(IsIgnore1 = true)]

??????? public int Id { get; set; }

??????? public string Name { get; set; }

??????? public string Age { get; set; }

??????? public string Address { get; set; }

??????? public string Area { get; set; }
??? }

2.3在创建SqlSugarClient对象中添加代码

                ConfigureExternalServices = new ConfigureExternalServices()
??????????????? {
                    //设置列相关的属性
??????????????????? EntityService = (property, column) =>
??????????????????? {
??????????????????????? var attributes = property.GetCustomAttributes(true);//get all attributes 
                        
                        //如果不清楚具体走了哪个自定义特性，可以打印出来看看
??????????????????????? foreach (var attribute in attributes)
??????????????????????? {
??????????????????????????? if (attribute is SugarTest1)
??????????????????????????? {
??????????????????????????? }
??????????????????????????? if (attribute is SugarTest2)
??????????????????????????? {
??????????????????????????? }
??????????????????????? }
??????????????????????? if (attributes.Any(it => it is SugarTest2))// by attribute set primarykey
??????????????????????? {
??????????????????????????? column.DbColumnName = "小列"; 
??????????????????????? }
??????????????????? },
                    
                    //设置表的属性
??????????????????? EntityNameService = (type, entity) =>
??????????????????? {
??????????????????????? var attributes = type.GetCustomAttributes(true);
??????????????????????? if (attributes.Any(it => it is SugarTest1))
??????????????????????? {
??????????????????????????? entity.DbTableName = "小表";
??????????????????????? }
??????????????????? }
??????????????? }

2.4添加创建表的代码，查看效果

断点打到2.3的位置上

//创建表
db.CodeFirst.SetStringDefaultLength(200).InitTables(typeof(Test));

3.实体不使用特性

创建对象的时候，根据规则，指定哪个字段主键，哪个字段自增；这样就不需要在实体添加特性

var?db=?new?SqlSugarClient(new?ConnectionConfig()
{
?DbType?=?SqlSugar.DbType.MySql,
?ConnectionString?=?Config.ConnectionString,
?sAutoCloseConnection?=?true,
?ConfigureExternalServices=new?ConfigureExternalServices()?{
????EntityService?=?(t,?column)?=>?
????{
????????if?(column.PropertyName.ToLower()?==?"id")?//是id的设为主键
????????{
????????????column.IsPrimarykey?=?true;
????????????if?(column.PropertyInfo.PropertyType?==?typeof(int))?//是id并且是int的是自增
????????????{
????????????????column.IsIdentity?=?true;
????????????}
????????}
????}
}
});

4.特性明细

下面是CRUD用到的特性，不包含建表的属性

注意：

• EntityInfo：关于数据库表的一些属性
• EntityColumnInfo：关于数据库表字段的一些属性

文档参考：配置实体

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