存储库模式实施经验

我正准备开始一个新的asp.net web项目,我将转向LINQ-to-SQL.我已经完成了一些工作,使用Mike Hadlow发现的一些信息来设置我的数据层,这些信息使用Interface和泛型为数据库中的每个表创建一个Repository.起初我认为这是一个有趣的方法.但是,现在我认为创建一个基本Repository类并继承它以为我需要访问的表创建一个TableNameRepository类可能更有意义.

哪种方法允许我以干净的可测试方式添加特定于表的功能？这是我的Repository实现以供参考.

public class Repository : IRepository where T : class, new()
{
    protected IDataConnection _dcnf;

    public Repository()
    {
        _dcnf = new DataConnectionFactory() as IDataConnection;
    }

    // Constructor injection for dependency on DataContext 
    // to actually connect to a database
    public Repository(IDataConnection dc)
    {
        _dcnf = dc;
    }

    /// 

    /// Return all instances of type T.
    /// 
    /// IEnumerable
    public virtual IEnumerable GetAll()
    {
        return GetTable;
    }

    public virtual T GetById(int id)
    {
        var itemParam = Expression.Parameter(typeof(T), "item");
        var whereExp = Expression.Lambda>
            (
                Expression.Equal(
                    Expression.Property(itemParam, PrimaryKeyName),
                    Expression.Constant(id)
                ), new ParameterExpression[] { itemParam }
            );
        return _dcnf.Context.GetTable().Where(whereExp).Single();
    }

    /// 

    /// Return all instances of type T that match the expression exp.
    /// 
    /// 
    /// IEnumerable
    public virtual IEnumerable FindByExp(Func exp)
    {
        return GetTable.Where(exp);
    }

    /// 
See IRepository.
    /// 
    public virtual T Single(Func exp)
    {
        return GetTable.Single(exp);
    }

    /// 
See IRepository.
    /// 
    public virtual void MarkForDeletion(T entity)
    {
        _dcnf.Context.GetTable().DeleteOnSubmit(entity);
    }

    /// 

    /// Create a new instance of type T.
    /// 
    /// T
    public virtual T Create()
    {
        //T entity = Activator.CreateInstance();
        T entity = new T();
        GetTable.InsertOnSubmit(entity);
        return entity;
    }

    /// 
See IRepository.
    public virtual void SaveAll()
    {
        _dcnf.SaveAll();
    }

    #region Properties
    private string PrimaryKeyName
    {
        get { return TableMetadata.RowType.IdentityMembers[0].Name; }
    }

    private System.Data.Linq.Table GetTable
    {
        get { return _dcnf.Context.GetTable(); }
    }

    private System.Data.Linq.Mapping.MetaTable TableMetadata
    {
        get { return _dcnf.Context.Mapping.GetTable(typeof(T)); }
    }

    private System.Data.Linq.Mapping.MetaType ClassMetadata
    {
        get { return _dcnf.Context.Mapping.GetMetaType(typeof(T)); }
    }
    #endregion
}

Frederik Ghe.. 5

您不应为每个表创建存储库.
相反,您应该为域模型中存在的每个"实体根"(或聚合根)创建一个存储库.您可以在此处了解有关该模式的更多信息并查看工作示例:

http://deviq.com/repository-pattern/

您不应为每个表创建存储库.
相反,您应该为域模型中存在的每个"实体根"(或聚合根)创建一个存储库.您可以在此处了解有关该模式的更多信息并查看工作示例:

http://deviq.com/repository-pattern/