确实,你不需要Linq,你总是可以不这样做,但你可能想要这样做。

林克提供了一种办法,可以表达根据可以查询的数据进行操作,然后我们能够根据数据状况开展其他行动。 它有意撰写,以便尽可能地分析这些数据是否属于专题收集、XML、数据库等。 归根结底,它总是以某种内层物体为作业,有一些手段在内层和最终来源之间转换,尽管有些约束比其他约束更进一步,将一些行动推向另一层。 例如,电话.Count() 最终可检索Count 财产,通过收集进行,并保持标记,向数据库发送查询,或者可能的话。

投管处提供了一种办法,可相互反映元件和数据库浏览量,而变数则反映在对面的变化中。

这完全属于上文“某些转换手段”的范围。 因此,Linq2SQL、EF和Linq2NHibern均履行林业局的作用和Linq供应商的作用。

Considering that Linq can work on collections you d have to be pretty perverse to create an ORM that couldn t support Linq at all (you d have to design your collections to not implement IEnumerable<T> and hence not work with foreach). More directly supporting it though means you can offer better support. At the very least it should make for more efficient queries. For example if an ORM gave us a means to get a Users object that reflected all rows in a users table, then we would always be able to do:

  int uID = (from u in Users where u.Username == "Alice" select u.ID).FirstOrDefault();

若不直接支持林克,则将<代码>Users 执行<编码>IQueryable<User>,即:

SELECT * FROM Users

后续行动:

while(dataReader.Read())
  yield return ConstructUser(dataReader);

后续行动:

foreach(var user in Users)
  if(user.Username == "Alice")
    return user.ID;
return 0;

实际上,这比这差一点。 在直接支助下,制作的KQry将:

SELECT TOP 1 id FROM Users WHERE username =  Alice 

然后C#就等于

return dataReader.Read() ? dataReader.GetInt32(0) : 0;

很显然,林克供应商越多地支持林克公司,如何更好地运作。

Linq is an in-language feature of C# and VB.NET and can also be used by any .NET language though not always with that same in-language syntax. As such, ever .NET developer should know it, and every C# and VB.NET developer should particularly know it (or they don t know C# or VB.NET) and that s the group NHibernate is designed to be used by, so they can depend on not needing to explain a whole bunch of operations by just implementing them the Linq way. Not supporting it in a .NET library that represents queryable data should be considered a lack of completeness at best; the whole point of an ORM is to make manipulating a database as close to non-DB related operations in the programming language in use, as possible. In .NET that means Linq supprt.

LINQ is a query language. It allows you to express queries in a way that is not tied in to your persistence layer.

您可能想到ORM 。

nHibernate, EF, LINQ2XML are all LINQ holder - 所有这些都允许你利用LINQ syntax获得数据来源m>。

首先,光是所有准则都不是管理办公室。 无论物体来自何方,都质问物体。

因此,你可以与Nhibernate使用LINQ,这是完全有意义的。

我认为,你误解了LINQ至LINQ至。