how to generate barcode c# code How It Works in Font

Painting Quick Response Code in Font How It Works

How It Works
QR Code ISO/IEC18004 Generation In None
Using Barcode encoder for Font Control to generate, create Quick Response Code image in Font applications.
www.OnBarcode.com
GTIN - 12 Creation In None
Using Barcode printer for Font Control to generate, create UPC-A image in Font applications.
www.OnBarcode.com
In Listing 3-2, we add three Students to the object context and save them to the database using SaveChanges().
Make PDF 417 In None
Using Barcode creator for Font Control to generate, create PDF 417 image in Font applications.
www.OnBarcode.com
Code128 Creation In None
Using Barcode creator for Font Control to generate, create USS Code 128 image in Font applications.
www.OnBarcode.com
QUERYING AN ENTITY DATA MODEL
USS Code 39 Encoder In None
Using Barcode generator for Font Control to generate, create ANSI/AIM Code 39 image in Font applications.
www.OnBarcode.com
GS1 - 13 Generation In None
Using Barcode generation for Font Control to generate, create GS1 - 13 image in Font applications.
www.OnBarcode.com
To retrieve the Students who are working on a Masters degree, we use the ExecuteStoreQuery() method with a parameterized SQL statement and a parameter set to Masters. We iterate through the returned collection of Students and print each of them. Here we use * in place of explicitly naming each column in the select statement. This works because the columns in the underlying table match the properties in the Student entity type. Entity Framework will match up the returned values to the appropriate properties. This works out fine in most cases, but if you have fewer columns returned from your query, Entity Framework will throw an exception during the materialization of the object. This can easily be fixed by adding dummy columns and values of the appropriate types to your query. If your SQL statement returns more columns than required to materialize the entity, Entity Framework will happily ignore the additional columns. There are some restrictions with the ExecuteStoreQuery() method. If you are using Table per Hierarchy inheritance and your SQL statement returns rows that could map to different derived types, Entity Framework will not be able to use the discriminator column to map the rows to the correct derived types. You will likely get a runtime exception because some rows don t contain the values required for the type being materialized. If an entity has a complex type property, then instances of the entity can t be returned using ExecuteStoreQuery(). However, ExecuteStoreQuery() can be used to return a collection of instances of a complex type. Returning instances of a complex type, which is supported, is subtly different from returning instances of an entity that contains a complex type, which is not supported. You can use ExecuteStoreQuery() to materialize objects that are not entities at all. For example, we could create a StudentName class that contains just first and last names of a student. If our SQL statement returned just these two strings, then we could use ExecuteStoreQuery<StudentName>() along with our SQL statement to get a collection of instances of StudentName. We ve been careful to use the phrase SQL statement rather than select statement because the ExecuteStoreQuery() method works with any SQL statement that returns a row set. This includes, of course, select statements, but also includes statements that execute stored procedures. There is a version of ExecuteStoreQuery() that takes a parameter that determines how the returned objects are merged into the object context. By default, ExecuteStoreQuery() uses the MegeOption.NoTracking, which means that the returned objects are not tracked in the object context. If you happened to retrieve an object that has the same entity key as an object that is already in the object context, you will get a fresh copy of the object. If you use this version of the ExecuteStoreQuery() method, the second parameter is the name of the entity set that contains the entity.
Encoding EAN 128 In None
Using Barcode creator for Font Control to generate, create EAN / UCC - 14 image in Font applications.
www.OnBarcode.com
Create ITF In None
Using Barcode encoder for Font Control to generate, create ANSI/AIM I-2/5 image in Font applications.
www.OnBarcode.com
3-3. Returning Objects from an Entity SQL Statement
Printing QR Code ISO/IEC18004 In Java
Using Barcode printer for Java Control to generate, create QR Code image in Java applications.
www.OnBarcode.com
QR-Code Printer In Java
Using Barcode maker for Android Control to generate, create QR Code JIS X 0510 image in Android applications.
www.OnBarcode.com
Problem
Data Matrix ECC200 Creation In None
Using Barcode generation for Office Excel Control to generate, create Data Matrix ECC200 image in Microsoft Excel applications.
www.OnBarcode.com
Barcode Reader In Java
Using Barcode Control SDK for BIRT Control to generate, create, read, scan barcode image in Eclipse BIRT applications.
www.OnBarcode.com
You want to execute an Entity SQL statement that queries your model and returns objects.
Drawing Denso QR Bar Code In None
Using Barcode maker for Software Control to generate, create QR Code image in Software applications.
www.OnBarcode.com
Barcode Creation In Objective-C
Using Barcode encoder for iPhone Control to generate, create Barcode image in iPhone applications.
www.OnBarcode.com
Solution
Code 39 Full ASCII Encoder In Java
Using Barcode encoder for Java Control to generate, create Code-39 image in Java applications.
www.OnBarcode.com
EAN / UCC - 14 Encoder In .NET Framework
Using Barcode maker for Reporting Service Control to generate, create UCC - 12 image in Reporting Service applications.
www.OnBarcode.com
Let s say you have a model like the one in Figure 3-4. The model contains a single Customer entity type. The Customer entity type has a Name and an Email property. You want to query this model using Entity SQL.
Barcode Recognizer In Java
Using Barcode scanner for Java Control to read, scan read, scan image in Java applications.
www.OnBarcode.com
UCC - 12 Maker In VB.NET
Using Barcode printer for .NET Control to generate, create EAN / UCC - 13 image in VS .NET applications.
www.OnBarcode.com
QUERYING AN ENTITY DATA MODEL
Barcode Creator In VS .NET
Using Barcode encoder for .NET framework Control to generate, create Barcode image in VS .NET applications.
www.OnBarcode.com
Creating ANSI/AIM Code 39 In C#.NET
Using Barcode drawer for .NET framework Control to generate, create Code39 image in .NET applications.
www.OnBarcode.com
Figure 3-4. A model with a Customer entity To query the model using Entity SQL, follow the pattern in Listing 3-3. The code in Listing 3-3 demonstrates executing and Entity SQL statement using both Object Services and EntityClient. Listing 3-3. Executing an Entity SQL statement using both Object Services and EntityClient using (var context = new EFRecipesEntities()) { var cus1 = new Customer { Name = "Robert Stevens", Email = "rstevens@mymail.com" }; var cus2 = new Customer { Name = "Julia Kerns", Email = "julia.kerns@abc.com" }; var cus3 = new Customer { Name = "Nancy Whitrock", Email = "nrock@myworld.com" }; context.Customers.AddObject(cus1); context.Customers.AddObject(cus2); context.Customers.AddObject(cus3); context.SaveChanges(); } // using object services using (var context = new EFRecipesEntities()) { Console.WriteLine("Customers..."); string esql = "select value c from Customers as c"; var customers = context.CreateQuery<Customer>(esql); foreach (var customer in customers) { Console.WriteLine("{0}'s email is: {1}", customer.Name, customer.Email); } } Console.WriteLine(); // using EntityClient using (var conn = new EntityConnection("name=EFRecipesEntities")) { Console.WriteLine("Customers..."); var cmd = conn.CreateCommand(); conn.Open();
Copyright © OnBarcode.com . All rights reserved.