merge two lists with WCF Services and Linq

Question

How do I merge two lists when using REST services? You can't use union with linq and dataservicequery so I'm not sure where to go.

The following doesn't work with dataservicequery...

var docQuery = (from docs in context.Documents.AsQueryable()
                        select new DocsColumns()
                        {
                            Title = docs.Title
                            //     Element = docs.Elements.Title 
                        })
                        .Union(from rules in context.Rules.AsQueryable()
                               select new DocsColumns()
                               {
                                   Title = rules.Title
                                   //    Element = rules.Elements.Title 
                               });

                               as DataServiceQuery<DocsColumns>;

This link doesn't help much either.... https://stackoverflow.com/questions/720609/merge-two-object-lists-with-linq

Any ideas? Really struggling on this one.

Answer 1

Using Linq, You can merge using below pseudo code :

using (DataContext context = new DataContext("<<Site Url>>"))
{

    EntityList<Item> allDocuments = context.GetList<Item>("Documents");
    EntityList<Item> allRules = context.GetList<Item>("Rules");

    List<Item> allDocumentItems = <<Select relevant docs from allDocuments>>;    
    List<Item> allRuleItems = <<Select relevant rules from allRules>>;

    IEnumerable<Item> mergedItems = allDocumentItems.Union(allRuleItems);
}

Note that Your source code must provide a declaration of an Item class, and that class must declare properties for each of the columns in the content type that your queries reference. For e.g.:

[ContentType(Name="Item", Id="0x01")]
public partial class Item
{
    [Column(Name = "Title", FieldType = "Text")] 
    public String Title { get; set; }
}