View source for LINQ to Sense/Net examples

[[Category:Developers]]
[[Category:Portal builders]]
{{FeatureInfo
|editions=wcm,ecm,comm
|fromversion=6.3
|wikicomplete=100%
|interest=developer,builder
}}
 
{{SNTOC}}

=Overview=
{{LeadImage|Linq-lead.png|LINQ to Sense/Net}}
'''Language-Integrated Query''' (LINQ) provides query capabilities for many types of data store. '''Sense/Net ECMS''' contains an implementation of this concept that provides a way to query against the Sense/Net [[Content Repository]]. The [[LINQ to Sense/Net]] article provides the overview and basics of the implementation of LINQ in Sense/Net ECMS. This article provides examples and best pratices for developers and portal builders for using LINQ to Sense/Net in [[Content View|Content Views]], [[How to create a ContentHandler|ContentHandlers]] or any source code related to Sense/Net.
{{clear}}

=Details=
The following examples demonstrate the power of [[LINQ to Sense/Net]] and provide best practices on how to use the feature.
{{info|To see a detailed list of the supported operations, see the [[LINQ to Sense/Net operations]] article.}}
==Simple field filtering==
====Strongly typed property====
<source lang="csharp">
Content.All.Where(c => c.Id == 1234); // content by identity
Content.All.Where(c => c.ModificationDate > DateTime.Now.AddDays(-1)); // content from the last 24 hours
Content.All.Where(c => c.DisplayName.StartsWith("{prefix}")); // content by display name prefix
</source>
====Content Field indexer====
<source lang="csharp">
Content.All.Where(c => (int)c["Id"] == 1234);
Content.All.Where(c => (string)c["Model"] == "Model 1");
</source>
====Content handler queries====
<source lang="csharp">
Content.All.Where(c => ((Site)c.ContentHandler).EnableClientBasedCulture == true); // casting
Content.All.OfType<Site>().Where(c => c.EnableClientBasedCulture == true)); // type filter using OfType
</source>
==Reference filtering==
<source lang="csharp">
Content.All.OfType<Article>().Where(c => c.Author == author); // filter by existence for a single reference field
Content.All.OfType<Article>().Where(c => c.Related.Contains(refArticle)); // filter by existence for a multi reference field
Content.All.OfType<Article>().Where(c => c.Author == null); // empty reference
</source>
==Type filtering==
Search for exact type:
<source lang="csharp">
Content.All.Where(c => c.ContentType.Name == "Group");
Content.All.Where(c => c.ContentType == ContentType.GetByName("Group"));
Content.All.Where(c => c.Type("Car"));
</source>

Search for derived types too:
<source lang="csharp">
Content.All.Where(c => c.ContentHandler is Group);
Content.All.Where(c => typeof(Group).IsAssignableFrom(c.ContentHandler.GetType()));
Content.All.Where(c => c.TypeIs("Car"));
</source>
==Ordering and Partitioning==
<source lang="csharp">
// content from last month, 9th page
Content.All.Where(c => c.ModificationDate > DateTime.Now.AddMonths(-1)).OrderByDescending(c => c.ModificationDate).Skip(80).Take(10); 
</source>

==Element operators==
<source lang="csharp">
Content.All.Where(c.Id == 1234).First(); // Load content that must exist.
Content.All.First(c.Id == 1234); // Load content that must exist.
Content.All.Where(c.Id == 1234).FirstOrDefault(); // Load content that may exist.
Content.All.FirstOrDefault(c.Id == 1234); // Load content that may exist.
</source>
==Quantifier==
<source lang="csharp">
Content.All.Any(c => c.InTree("/Root/.../MyWorkspace") && c.ContentHandler is MyContentType));
</source>
==Aggregation==
<source lang="csharp">
Content.All.Where(c => c.InTree("/Root/.../MyWorkspace") && c.ContentHandler is MyContentType)).Count();
Content.All.Count(c => c.InTree("/Root/.../MyWorkspace") && c.ContentHandler is MyContentType));
</source>
==Projection==
Please note that we use the ''AsEnumerable'' method here as described in the [[LINQ to Sense/Net operations#Not supported operations|LINQ to Sense/Net operations]] article.
<source lang="csharp">
var items = Content.All.Where(c => c.Id < 8).AsEnumerable().Select(c => new { Id = c.Id, FriendlyName = c.DisplayName });
foreach (var item in items)
	Console.WriteLine("Id: {0}, Name: {1}", item.Id, item.FriendlyName);
</source>
==Grouping==
<source lang="csharp">
var groups = Content.Load("/Root/IMS/BuiltIn/Portal").Children.OrderBy(c => c.Name).AsEnumerable().GroupBy(c => c.Name.First());
foreach (var group in groups)
{
	Console.WriteLine("{0}:", group.Key).AppendLine();
	foreach (var item in group)
		Console.WriteLine(item.Name);
}
</source>

The result of the code above is the following:
<source lang="text">
A:
Administrator
Administrators
C:
Creators
E:
Everyone
L:
LastModifiers
V:
Visitor
</source>

==Sense/Net specific LINQ methods==
Content from multiple places in one list
<source lang="csharp">
Content.All.Where(c => c.InTree("/Root/...path1") 
	|| c.InTree("/Root/...path2") 
	|| c.InFolder("/Root/...path3")).OrderByDescending(c => c.ModificationDate).Take(5);
</source>

=Related links=
*[[LINQ to Sense/Net]]
*[[LINQ to Sense/Net operations]]
*[[Content Repository]]