LINQ presentation
Download as pptx, pdf2 likes1,051 views
LINQ presentation by Chi Khang HCMC Open University 2009
![LINQ TO DATASETDATASET ?LINQ to DataSet gi炭p truy v畉n 畛i t動畛ng Dataset d畛 dng v nhanh ch坦ngvar cus = from c in customersDataset.Tables["Customers"].AsEnumerable() select c["CustomerID"];foreach (var c in cus){ Console.WriteLine("{0}", c);}](https://image.slidesharecdn.com/linqpresentation-110301102741-phpapp01/85/LINQ-presentation-19-320.jpg)
More Related Content
Viewers also liked (20)
Similar to LINQ presentation (20)
LINQ presentation
- 1. LINQTr畉nCh鱈 KhangMicrosoft Student PartnersEmail: khangtran1990@hotmail.com
- 3. Ph但n lo畉i
- 5. LINQ to XML
- 7. LINQ to SQL
- 8. ADO.NET
- 10. LINQ vs ADO.NET
- 11. DEMOD畛 li畛u c坦 th畛 動畛c l動u tr畛 畛 nhi畛u n董iDatabase(SQL Server,Oracle )
- 12. XML files
- 13. File 油(Access, Excel )C叩ch giao ti畉p ?
- 14. KHI NI畛M LINQL ng担n ng畛 truy v畉n 動畛c t鱈ch h畛p vo ng担n ng畛 l畉p tr狸nh (VB, C#, ).
- 15. 動a ra kh畉 nng l畉p tr狸nh m畛i trong .NET-Gi畉i ph叩p l畉p tr狸nh h畛p nh畉tfrom customer in Customerswhere油customer.Name == "Foysal"select customer
- 16. LINQ TO OBJECTS畛 d畛ng LINQ 畛 truy v畉n t畉p h畛p c叩c 畛i t動畛ng d動畛i d畉ng IEnumerable ho畉c IEnumerable<T>Without LINQWith LINQList<Students> MaleStudents = new List<Students>();Foreach(Students student in Students){ if(student.sex == male) { MaleStudents.Add(student ); }}IEnumerable <Students> MaleStudents =from student in Studentswhere student.sex==maleselect student;
- 17. LINQ TO XML XmlDocumentdoc = newXmlDocument();XmlElementbooks = doc.CreateElement("books");XmlElement author = doc.CreateElement("author");author.InnerText = "Fabrice Marguerie";XmlElement price= doc.CreateElement(price");author2.InnerText = 80;XmlElement publishyear = doc.CreateElement(publishyear");author3.InnerText = 2008";XmlElementtitle = doc.CreateElement("title");title.InnerText = ABC";XmlElementbook = doc.CreateElement("book");book.AppendChild(author1);book.AppendChild(author2);book.AppendChild(author3);book.AppendChild(title);books.AppendChild(book);doc.AppendChild(books);XDocument xmlbooks = newXDocument(newXDeclaration("1.0", "UTF-16", "yes"),newXElement("books",newXElement("book", newXAttribute("id","B01"),newXElement("author", "Fabrice Marguerie"),newXElement("price", 80),newXElement("publishyear", 2008),newXElement("title", "ABC"))));<?xmlversion="1.0"encoding="utf-8" ?><books> <book id = B01> <title>ABC</title> <author>Fabrice Marguerie </author><price>80</price><pulishyear>2008</pulishyear> </book></books>
- 18. LINQ TO XML Cung c畉p 1 c担ng c畛 m畉nh m畉 trong vi畛c truy v畉nXMLvar books = from b in xmlbooks.Elements("book") where(String)b.Element("price") == 80 selectnew { title = (String)b.Element("tilte"), author = (String)b.Element("author") };foreach (var book in books) {Console.WriteLine(book);}
- 19. LINQ TO DATASETDATASET ?LINQ to DataSet gi炭p truy v畉n 畛i t動畛ng Dataset d畛 dng v nhanh ch坦ngvar cus = from c in customersDataset.Tables["Customers"].AsEnumerable() select c["CustomerID"];foreach (var c in cus){ Console.WriteLine("{0}", c);}
- 20. LINQ TO SQLLINQ to SQL l m畛t phi棚n b畉n Object-Relational Mapping (ORM).DatabaseDataContextTableClassViewClassColumnField / PropertyRelationshipField / PropertyStored ProcedureMethod
- 21. L畛pDataContextL m畛t class k畉tn畛i畉nCSDL 畛 SQL Server
- 22. Chuy畛n c但u truy v畉n thnh c但u l畛nh SQL
- 23. 畉m nh畉n vi畛c t動董ng t叩c v畛i CSDL
- 24. Thay 畛i CSDLth担ng qua ph動董ng th畛c SubmitChanges().LINQTOSQLNorthwindDataContext db = newNorthwindDataContext();varquery = from c in db.Customers wherec.City == "London"selectnew { Name = c.ContactName, Country = c.Country, City = c.City };
- 25. C畉U TRC LINQ TO SQLfrom c in db.Customerswhere c.City == "London"select new {Name, Phone};db.Customers.InsertOnSubmit(c1);c2.City = Seattle";db.Customers.DeleteOnSubmit(c3);SELECT CompanyName, PhoneFROM CustomersWHERE City == 'London'INSERT INTO CustomersUPDATE CustomersDELETE FROM Customers
- 26. TransactionTransactionl m畛t d畛ch v畛 nh畉m 畉m b畉o r畉ng m畛t t畉p c叩c thao t叩c 畛c l畉p s畉 動畛c th畛c thi nh動 m畛t 董n v畛 duy nh畉tNorthwindDataContext db = newNorthwindDataContext(); using(TransactionScope ts = newTransactionScope()){ try { Productprod1 = db.Products.First(p => p.ProductID == 4); Productprod2 = db.Products.First(p => p.ProductID == 5);prod1.UnitsInStock -= 3;prod2.UnitsInStock -= 5;db.SubmitChanges();ts.Complete();}catch(Exception e){ Console.WriteLine(e.Message); Console.WriteLine("Error submitting changes,all changes rolled back."); } }
- 27. DeferredExecutionvar q = from d in db.Doctors whered.City == "London"selectd;if(orderByLocation){q = from d in qorderbyd.Country, d.Cityselectd;}elseif (orderByName){q = from d in qorderby d.DoctorNameselect d;}foreach(Doctor d in q) Console.WriteLine(d.DoctorName);
- 28. ADO.NET
- 29. Truyc畉pCSDLv畛i ADO.NETSqlConnection connection = new SqlConnection();connection.Open();SqlCommandcmd = new SqlCommand( Select Name, Phone From Customers Where City = @city );cmd.Parameters.AddWithValue(@city, London);Datareaderdr = connection.Execute(cmd);While (dr.Read()){ string name = dr.GetString(0); string phone = dr.GetString(1);DateTime date = dr.GetDateTime(2);}dr.Close();Connection.Close();Chu畛i truy v畉nX叩c畛nhki畛ud畛li畛uk畉tqu畉
- 32. LINQvsADO.NETLINQ l t畉p m畛 r畛ng cho ph辿p vi畉t c叩c c但u truy v畉n ngay trong c叩c ng担n ng畛 l畉p tr狸nh. ADO.NET l c担ng ngh畛 cho ph辿p c叩c 畛ng d畛ng c坦 th畛 k畉t n畛i v lm vi畛c v畛i c叩c lo畉i CSDL kh叩c nhauLINQ kh担ng ph畉i l m畛t c担ng ngh畛 動畛c t畉o ra 畛 thay th畉 ADO.NET
- 33. DEMO
- 34. C畉m 董n !