Question

I am struggling with converting multi-rows values which are belong to the same user into collection.

Here is a simple scenario.

users Table:userid, password

address Table:address, userid

Users Table and Address Table are one-to-many related–one user might have multi-addresses.
Assume the User’s ID is 1001 while he/she have two addresses one is in Auckland and another one is Wellington.
I would like select both of them together with user’s id.
1001 Auckland
1001 Wellington
So the question is are there any approach is able to put these two value into collection like list.

public class UserDetails{
    private List<String> _Address
    public string userid{get;set;}
    public List<String> Address{
    get{retrun _Address;}
    set{_Address=value;}
}
}

var user_address= from _user in users 

                  join _address in address on _user.userid=_address.userid

                  select new userDetails{
                  userid=_user.userid
                  **Address.add()**
};

Does anyone know how to construct the List in the LINQ and call the add method.
I want to put the list object into one row so that avoid the redundancy of userid.

Thanks for your help.

Answer 1

Maybe something like this:

var user_address= from _user in users 
                  select new userDetails{
                  userid=_user.userid,
                  Address=(from _address in address
                           where _user.userid=_address.userid
                           select _address.:address
                           ).ToList()
};

You do not have to join the address table.