Procedura: compilare una stringa di connessione EntityConnection
In questo argomento viene fornito un esempio di come compilare un oggetto EntityConnection.
Per eseguire il codice in questo esempio
Aggiungere il modello Sales di AdventureWorks al progetto e configurare il progetto per l'utilizzo di Entity Framework. Per altre informazioni, vedere Procedura: Usare la procedura guidata di Entity Data Model.
Nella tabella codici per l'applicazione aggiungere le istruzioni
using
seguenti (Imports
in Visual Basic):using System; using System.Collections.Generic; using System.Collections; using System.Data.Common; using System.Data; using System.IO; using System.Data.SqlClient; using System.Data.EntityClient; using System.Data.Metadata.Edm;
Imports System.Collections.Generic Imports System.Collections Imports System.Data.Common Imports System.Data Imports System.IO Imports System.Data.SqlClient Imports System.Data.EntityClient Imports System.Data.Metadata.Edm
Esempio
Nell'esempio seguente viene inizializzato l'oggetto System.Data.SqlClient.SqlConnectionStringBuilder per il provider sottostante, quindi viene inizializzato l'oggetto System.Data.EntityClient.EntityConnectionStringBuilder, che viene passato al costruttore di EntityConnection.
// Specify the provider name, server and database.
string providerName = "System.Data.SqlClient";
string serverName = ".";
string databaseName = "AdventureWorks";
// Initialize the connection string builder for the
// underlying provider.
SqlConnectionStringBuilder sqlBuilder =
new SqlConnectionStringBuilder();
// Set the properties for the data source.
sqlBuilder.DataSource = serverName;
sqlBuilder.InitialCatalog = databaseName;
sqlBuilder.IntegratedSecurity = true;
// Build the SqlConnection connection string.
string providerString = sqlBuilder.ToString();
// Initialize the EntityConnectionStringBuilder.
EntityConnectionStringBuilder entityBuilder =
new EntityConnectionStringBuilder();
//Set the provider name.
entityBuilder.Provider = providerName;
// Set the provider-specific connection string.
entityBuilder.ProviderConnectionString = providerString;
// Set the Metadata location.
entityBuilder.Metadata = @"res://*/AdventureWorksModel.csdl|
res://*/AdventureWorksModel.ssdl|
res://*/AdventureWorksModel.msl";
Console.WriteLine(entityBuilder.ToString());
using (EntityConnection conn =
new EntityConnection(entityBuilder.ToString()))
{
conn.Open();
Console.WriteLine("Just testing the connection.");
conn.Close();
}
' Specify the provider name, server and database.
Dim providerName As String = "System.Data.SqlClient"
Dim serverName As String = "."
Dim databaseName As String = "AdventureWorks"
' Initialize the connection string builder for the
' underlying provider.
Dim sqlBuilder As New SqlConnectionStringBuilder()
' Set the properties for the data source.
sqlBuilder.DataSource = serverName
sqlBuilder.InitialCatalog = databaseName
sqlBuilder.IntegratedSecurity = True
' Build the SqlConnection connection string.
Dim providerString As String = sqlBuilder.ToString()
' Initialize the EntityConnectionStringBuilder.
Dim entityBuilder As New EntityConnectionStringBuilder()
'Set the provider name.
entityBuilder.Provider = providerName
' Set the provider-specific connection string.
entityBuilder.ProviderConnectionString = providerString
' Set the Metadata location.
entityBuilder.Metadata = "res://*/AdventureWorksModel.csdl|res://*/AdventureWorksModel.ssdl|res://*/AdventureWorksModel.msl"
Console.WriteLine(entityBuilder.ToString())
Using conn As New EntityConnection(entityBuilder.ToString())
conn.Open()
Console.WriteLine("Just testing the connection.")
conn.Close()
End Using