MICROSOFT VISUAL C 2008 STEP BY STEP PHẦN 6 POTX

Microsoft Visual C# 2010 Step by Step (Microsoft Press 2010) or Michael Halvorson’s Microsoft Visual Basic 2010 Step by Step (Microsoft Press 2010).With a heavy focus on database concepts, this book assumes that you[r]

String areaCode = phoneNumber.DelimSubstring("-", 1);Visual BasicDim phoneNumber As String = "206-555-1234"Dim areaCode As String = phoneNumber.DelimSubstring("-", 1)The Entity Framework includes extension methods for common Entity SQL clauses, includ-ing Select, GroupBy, and Union. These met[r]

176 Microsoft ADO.NET 4 Step by StepC#// Build the selection query.SqlDataAdapter unitAdapter = new SqlDataAdapter();SqlCommand unitCommand = new SqlCommand( "SELECT * FROM UnitOfMeasure", linkToDB);unitAdapter.SelectCommand = unitCommand;// Build the insertion query.unitCommand[r]

tionality for the sample application. Locate the GetConnectionString function, a routine that uses a SqlConnectionStringBuilder to create a valid connection string to the sample database. It currently includes the following statements:builder.DataSource = "(local)\SQLExpress" builder.InitialCatalog[r]

166 Microsoft ADO.NET 4 Step by Step4. Just after the “Read the next set, which contains the orders” comment, add the follow-ing code:customerReader.NextResult() Do While (customerReader.Read = True) oneOrder = New OrderInfo oneOrder.ID = CLng(customerReader!ID) oneOrd[r]

186 Microsoft ADO.NET 4 Step by StepTable and Column MappingSometimes it isn’t convenient or even possible to use the same table and column names between your local DataTable and the external database table, view, or generated results it represents. In such situations, use the S[r]

C#// Commit the transaction.envelope.Commit();// Rollback the transaction.envelope.Rollback();Visual Basic' Commit the transaction.envelope.Commit()' Rollback the transaction.envelope.Rollback()You should always call Commit or Rollback explicitly. If you dispose of the object or allow it to g[r]

if (LocalServer.Checked == true) connection.DataSource = "(local)"; else connection.DataSource = ServerName.Text; if (IsExpressEdition.Checked == true) connection.DataSource += @"\SQLEXPRESS";This code defines the main SQL Server data source. The code differentiates between the Express Edition (an[r]

case a MemoryStream instance. The remaining code in the event handler moves the XML content from the stream to an on-form text box. Chapter 7 Saving and Restoring Data 1176. Run the program. Use the fields in the upper-right corner of the form to alter the XML content and then click Generate to produ[r]

C#SqlConnection linkToDB = new SqlConnection(connectionString);linkToDB.Open();string sqlText = @"UPDATE WorkTable SET ProcessedOn = GETDATE() WHERE ProcessedOn IS NULL";SqlCommand dataAction = new SqlCommand(sqlText, linkToDB);Visual BasicDim linkToDB As New SqlConnection(connectionString)li[r]

AddName.Text = CStr(stateReader!FullName) AddAbbreviation.Text = CStr(stateReader!Abbreviation) Else ' No custom state record. AddName.Clear() AddAbbreviation.Clear() End If If (stateReader IsNot Nothing) Then stateReader.Close()This code uses the OpenReader function from step 5 to obtain[r]

The command object includes the ExecuteNonQuery method for running queries with no return results; the ExecuteScalar method, which returns a single result; and ExecuteReader, which returns a single-pass data reader, EntityDataReader. What is missing is the data adapter with its capability to move in[r]

names. This is probably not correctSELECT FROM Customer But this is valid with its pluralized name SELECT FROM Customers Chapter 15 Querying Data in the Framework 247The SELECT clause is a comma-delimited list of the values to be returned in each result row. In Entity SQL, every reference to a field[r]

Chapter 16Understanding Entities Through ObjectsAfter completing this chapter, you will be able to:Access the properties of an entity through a standard object instanceAdd, update, and delete database content by modifying object propertiesCarry out query-like actions using standard meth[r]

content of code generation items and how to modify them, search for “Generated Code Overview” within the Visual Studio online help.SummaryThis chapter continued the overview of the Entity Framework by introducing the ADO.NET Entity Data Model Designer and its associated database import[r]

C#infoSet.WriteXml(targetFile, XmlWriteMode.WriteSchema);Visual BasicinfoSet.WriteXml(targetFile, XmlWriteMode.WriteSchema)Other XmlWriteMode enumeration members include IgnoreSchema (don’t include the schema, which is the same as leaving off the second argument) and DiffGram (a special forma[r]

generate a SQL Server database with all needed tables and supporting elements. Use of the wiz-ard is beyond the scope of this book. For information on this tool, search for “Generate Database Wizard” in the Visual Studio 2010 online help.Understanding the Storage ModelThe storage model identi[r]

206 Microsoft ADO.NET 4 Step by StepProcessing with a Distributed Transaction: C#Note This exercise uses the “Chapter 12 CSharp” sample project and continues from where the previous exercise in this chapter left off.1. Open the code for the AccountTransfe r class. Locate the Tra[r]

226 Microsoft ADO.NET 4 Step by StepNote The wizard’s capability to build a model from an existing database can be limited by se-curity rights and restrictions imposed on your database account. Make sure you have sufficient rights to the database tables and elements that y[r]

Storing Rows in a Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Microsoft is interested in hearing your feedback so we can continually improve our books and learning resources for you. To participate in a brief online survey, please visit: www.microsoft.c[r]