Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
231 views
in Technique[技术] by (71.8m points)

c# - inner join in linq to entities

I have entity called Customer and it has three properties:

public class Customer {
    public virtual Guid CompanyId;
    public virtual long Id;
    public virtual string Name;
}

I have also entity called Splitting and it has three properties:

public class Splitting {
    public virtual long CustomerId;
    public virtual long Id;
    public virtual string Name;
}

Now I need to write a method that gets companyId and customerId. The method should return list of splitting that relates to the specific customerId in the companyId. Something like this:

public IList<Splitting> get(Guid companyId, long customrId) {    
    var res=from s in Splitting 
            from c in Customer 
            ...... how to continue?

    return res.ToList();
}
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)
var res = from s in Splitting 
          join c in Customer on s.CustomerId equals c.Id
         where c.Id == customrId
            && c.CompanyId == companyId
        select s;

Using Extension methods:

var res = Splitting.Join(Customer,
                 s => s.CustomerId,
                 c => c.Id,
                 (s, c) => new { s, c })
           .Where(sc => sc.c.Id == userId && sc.c.CompanyId == companId)
           .Select(sc => sc.s);

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...