How entities are loaded in EF

How to load an entity:

1. Greedy loading (eager loading)

2. Deferred load (lazy loading)

3. Display loading (explicit loading)

Greedy load implementations are implemented by the Include method

1 using(varContext =NewBloggingcontext ())2 {3     //Load all blogs and related posts4     varBLOGS1 =context. Blogs5. Include (b =b.posts)6                           . ToList ();7 8     //Load One blogs and its related posts9     varBlog1 =context. BlogsTen. Where (b = B.name = ="ADO Blog") One. Include (b =b.posts) A                         . FirstOrDefault (); -  -     //Load all blogs and related posts the     //using a string to specify the relationship -     varBLOGS2 =context. Blogs -. Include ("Posts") -                           . ToList (); +  -     //Load One blog and its related posts +     //using a string to specify the relationship A     varBLOG2 =context. Blogs at. Where (b = B.name = ="ADO Blog") -. Include ("Posts") -                         . FirstOrDefault (); -}

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Deferred loading is implemented with the virtual keyword (this is not possible when the EF framework disables lazy loading)

1  Public classBlog2 { 3      Public intBlogId {Get;Set; } 4      Public stringName {Get;Set; } 5      Public stringURL {Get;Set; } 6      Public stringTags {Get;Set; } 7 8      Public VirtualIcollection<post> Posts {Get;Set; } 9 }Ten  One //Disable Lazy loading A  Public classBloggingcontext:dbcontext - { -      PublicBloggingcontext () the     { -          This. configuration.lazyloadingenabled =false; -     } -}

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When lazy loading is disabled or when lazy loading is not used, managed data can still be obtained by displaying the load

1 using(varContext =NewBloggingcontext ())2 {3     varPost = context. Posts.find (2);4 5     //Load The blog related to a given post6Context. Entry (POST). Reference (p =p.blog). Load ();7 8     //Load The blog related to a given post using a string9Context. Entry (POST). Reference ("Blog"). Load ();Ten  One     varBlog = context. Blogs.find (1); A  - //A couple of long use collection -     //Load The posts related to a given blog theContext. Entry (blog). Collection (p =p.posts). Load (); -  -     //Load The posts related to a given blog -     //using a string to specify the relationship +Context. Entry (blog). Collection ("Posts"). Load (); - } +  A //use the Query method to do some filtering at using(varContext =NewBloggingcontext ()) - { -     varBlog = context. Blogs.find (1); -  -     //Load The posts with the ' entity-framework ' tag related to a given blog - context. Entry (blog) in. Collection (b =b.posts) -         . Query () to. Where (p = p.tags.contains ("entity-framework") +         . Load (); -  the     //Load The posts with the ' entity-framework ' tag related to a given blog *     //using a string to specify the relationship $ context. Entry (blog)Panax Notoginseng. Collection ("Posts") -         . Query () the. Where (p = p.tags.contains ("entity-framework") +         . Load (); A}

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How entities are loaded in EF