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This article mainly introduces "how to realize the linq cascade operation". In the daily operation, I believe that many people have doubts about how to realize the linq cascade operation. The editor consulted all kinds of materials and sorted out a simple and easy-to-use operation method. I hope it will be helpful to answer the doubt of "how to realize the linq cascade operation". Next, please follow the editor to study!

1. I first built two new tables, one is category, the other is product.

Category table

Product table

two。 Then add the linq cascade:

ALTER TABLE product ADD CONSTRAINT [FK_ product _ Key] FOREIGN KEY (catid) REFERENCES Category (catid) GO

3. Code: the added linq cascading code is:

Category_Product_ContextDataContext cpcontext = new Category_Product_ContextDataContext (System.Configuration.ConfigurationManager.ConnectionStrings ["TestConnectionString"] .ToString ()); / cascading add Category cat=new Category (). {Catid = 1005, CatName = "Design", CatDescription = "many designs"} Product p1 = new Product ()... {ProductName = "graphic design", ProductDescripton = "big design", Category=cat}; Product p2 = new Product (). {ProductName = "stereoscopic design", ProductDescripton = "new computer", Category=cat} Product p3 = new Product ()... {ProductName = "interior design", ProductDescripton = "interior design forest", Category = cat}; Product p4 = new Product (). {ProductName = "product design", ProductDescripton = "forest", Category = cat} Product P5 = new Product ()... {ProductName = "Architectural Design", ProductDescripton = "in", Category = cat}; cpcontext.Categories.InsertOnSubmit (cat); cpcontext.SubmitChanges ()

Deleted linq cascading code:

The principle of deletion is: delete the slave table first and then delete the master table

Category_Product_ContextDataContext cpcontext = new Category_Product_ContextDataContext (System.Configuration.ConfigurationManager.ConnectionStrings ["TestConnectionString"] .ToString ()); Category singlecats = cpcontext.Categories.Single (p = > p.Catid = = 1004); foreach (Product p in cpcontext.Products.Where (p = > p.CatId = = 1004)) / delete from table. {cpcontext.Products.DeleteOnSubmit (p) } cpcontext.Categories.DeleteOnSubmit (singlecats); / / delete the main table cpcontext.SubmitChanges (); at this point, the study on "how to implement the linq cascading operation" is over, hoping to solve everyone's doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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