c# - 是否可以使用反射从通用实体访问属性(按名称)？

Question

我想从泛型类 T 创建一个泛型查询。有没有办法使用反射或其他方法来实现类似的查询？

public class DAO<T>        
    where T : class
{
    protected ObjectSet<T> Entities
    {
        get
        {
            return myContextThatIsInSomewhere.CreateObjectSet<T>();
        }
    }

    public IList<T> SelectBy(object fields)
    {
        if (fields == null)
        {
            throw new ArgumentNullException("fields");
        }

        var query = from e in this.Entities                    
                    select e;

        foreach (var field in fields.GetType().GetFields())
        {
            query = from e in this.Entities
                    // Do something like that:                   
                    where e.(field.Name) == field.GetValue()
                    select e;         
        }

        return query.ToList();
    }
}

Answer 1

制作SelectBy采取Expression<Func<T, bool>> (称之为 predicate )然后你就可以说

var query = this.Entities.Where(predicate);

您可以传递 Expression<Func<T, bool>> 的实例通过说

x => x.Foo == foo

例如。