Linq2Sql relationships and WCF serialization problem
here is my scenario i got
Table1
- id
- name
Table2
- id
- family
- fid
with one to many relationship set between Table1. id and Table2.fid
now here is my WCF service Code
[OperationContract]
public List<Table1> GetCustomers(string numberToFetch)
{
using (DataClassesDataContext开发者_StackOverflow社区 context = new DataClassesDataContext())
{
return context.Table1s.Take(int.Parse(numberToFetch)).ToList( );
}
}
and my ASPX page Code
<body xmlns:sys="javascript:Sys"
xmlns:dataview="javascript:Sys.UI.DataView">
<div id="CustomerView"
class="sys-template"
sys:attach="dataview"
dataview:autofetch="true"
dataview:dataprovider="Service2.svc"
dataview:fetchParameters="{{ {numberToFetch: 2} }}"
dataview:fetchoperation="GetCustomers">
<ul>
<li>{{family}}</li>
</ul>
</div>
though i set serialization mode to Unidirectional in Linq2Sql designer i am not able to get the family value and all what i get is this in firebug
{"d":[{"__type":"Table1:#","id":1,"name":"asd"},{"__type":"Table1:#","id":2,"name":"wewe"}]}
any help would be totally appreciated
Well, the point is: your method GetCustomers only ever selects from Table1 - I don't see any reference at all to Table2, where your Family column is located......
You need to check into Linq-to-SQL JOIN's and how to fetch data from a joined table into your result set.
Something along the lines of:
[DataContract]
class JoinedResult
{
[DataMember]
public int Table1ID { get; set; }
[DataMember]
public string Table1Name { get; set; }
[DataMember]
public string Table2Family { get; set; }
}
[OperationContract]
public List<JoinedResult> GetCustomers(int numberToFetch)
{
using (DataClassesDataContext context = new DataClassesDataContext())
{
var q = from t1 in context.Table1
join t2 in context.Table2 on t1.id = t2.fid
select new JoinedResult
{ Table1ID = t1.ID,
Table1Name = t1.Name,
Table2Family = t2.Family };
return q.Take(numberToFetch).ToList();
}
}
and btw: you should really make numberToFetch an INT parameter! Let the caller make the conversion......
UPDATE: if you don't want to explicitly include the second table to be queried, you could instead add a DataLoadOption to your context:
DataLoadOptions dlo = new DataLoadOptions();
dlo.LoadWith<Table1>(t => t.Table2);
context.LoadOptions = dlo;
In that case, you tell LINQ to always include all elements from Table2 when it loads anything from Table1 - that should work, too.
加载中,请稍侯......
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