EntityConnection Class

Reference

Definition

Namespace:: System.Data.EntityClient

Assembly:: System.Data.Entity.dll

Important

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Contains a reference to a conceptual model and a data source connection. This class cannot be inherited.

public ref class EntityConnection sealed : System::Data::Common::DbConnection

public sealed class EntityConnection : System.Data.Common.DbConnection

type EntityConnection = class
    inherit DbConnection

Public NotInheritable Class EntityConnection
Inherits DbConnection

Inheritance: Object

MarshalByRefObject

Component

DbConnection
EntityConnection

Remarks

To avoid inadvertently putting objects such as System.Data.Common.CommandTrees and ObjectContext out of sync with their metadata, EntityConnection must lock its metadata. No changes to the connection string are allowed after the metadata is locked. The following are two scenarios in which metadata is locked:

The EntityConnection instance is constructed through the parameterless constructor, or through the EntityConnection(String) constructor, which accepts a connection string. In either case the connection string might be changed multiple times before the connection is opened. Calling Open or GetMetadataWorkspace locks the metadata.
The EntityConnection instance is constructed through the EntityConnection(MetadataWorkspace, DbConnection) constructor, which accepts a MetadataWorkspace and a DbConnection. In this case, the metadata is locked at construction time. No changes to the connection string are ever allowed.

When metadata is loaded, the EntityConnection verifies that the conceptual model, the storage model, and the mapping file are all present.

For code examples, see Working with EntityClient.

Constructors

EntityConnection()	Initializes a new instance of the EntityConnection class.
EntityConnection(MetadataWorkspace, DbConnection)	Initializes a new instance of the EntityConnection class with a specified MetadataWorkspace and DbConnection.
EntityConnection(String)	Initializes a new instance of the EntityConnection class, based on the connection string.

Properties

CanCreateBatch	Gets a value that indicates whether this DbConnection instance supports the DbBatch class. (Inherited from DbConnection)
CanRaiseEvents	Gets a value indicating whether the component can raise an event. (Inherited from Component)
ConnectionString	Gets or sets the EntityConnection connection string.
ConnectionTimeout	Gets the number of seconds to wait when attempting to establish a connection before ending the attempt and generating an error.
Container	Gets the IContainer that contains the Component. (Inherited from Component)
Database	Gets the name of the current database, or the database that will be used after a connection is opened.
DataSource	Gets the name or network address of the data source to connect to.
DbProviderFactory	Gets the DbProviderFactory for this DbConnection. (Inherited from DbConnection)
DesignMode	Gets a value that indicates whether the Component is currently in design mode. (Inherited from Component)
Events	Gets the list of event handlers that are attached to this Component. (Inherited from Component)
ServerVersion	Gets a string that contains the version of the data source to which the client is connected.
Site	Gets or sets the ISite of the Component. (Inherited from Component)
State	Gets the ConnectionState property of the underlying provider if the EntityConnection is open. Otherwise, returns Closed.
StoreConnection	Provides access to the underlying data source connection that is used by the EntityConnection object.

Methods

BeginDbTransaction(IsolationLevel)	When overridden in a derived class, starts a database transaction. (Inherited from DbConnection)
BeginDbTransactionAsync(IsolationLevel, CancellationToken)	Asynchronously starts a database transaction. (Inherited from DbConnection)
BeginTransaction()	Begins a transaction by using the underlying provider.
BeginTransaction(IsolationLevel)	Begins a transaction with the specified isolation level by using the underlying provider.
BeginTransactionAsync(CancellationToken)	Asynchronously begins a database transaction. (Inherited from DbConnection)
BeginTransactionAsync(IsolationLevel, CancellationToken)	Asynchronously begins a database transaction. (Inherited from DbConnection)
ChangeDatabase(String)	Not supported.
ChangeDatabaseAsync(String, CancellationToken)	Asynchronously changes the current database for an open connection. (Inherited from DbConnection)
Close()	Closes the connection to the database.
CloseAsync()	Asynchronously closes the connection to the database. (Inherited from DbConnection)
CreateBatch()	Returns a new instance of the provider's class that implements the DbBatch class. (Inherited from DbConnection)
CreateCommand()	Creates a new instance of an EntityCommand, with the Connection set to this EntityConnection.
CreateDbBatch()	When overridden in a derived class, returns a new instance of the provider's class that implements the DbBatch class. (Inherited from DbConnection)
CreateDbCommand()	When overridden in a derived class, creates and returns a DbCommand object associated with the current connection. (Inherited from DbConnection)
CreateObjRef(Type)	Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object. (Inherited from MarshalByRefObject)
Dispose()	Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources. (Inherited from DbConnection)
Dispose(Boolean)	Releases the unmanaged resources used by the DbConnection and optionally releases the managed resources. (Inherited from DbConnection)
DisposeAsync()	Asynchronously diposes the connection object. (Inherited from DbConnection)
EnlistTransaction(Transaction)	Enlists this EntityConnection in the specified transaction.
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetLifetimeService()	Obsolete. Retrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject)
GetMetadataWorkspace()	Returns the MetadataWorkspace associated with this EntityConnection.
GetSchema()	Returns schema information for the data source of this DbConnection. (Inherited from DbConnection)
GetSchema(String, String[])	Returns schema information for the data source of this DbConnection using the specified string for the schema name and the specified string array for the restriction values. (Inherited from DbConnection)
GetSchema(String)	Returns schema information for the data source of this DbConnection using the specified string for the schema name. (Inherited from DbConnection)
GetSchemaAsync(CancellationToken)	This is an asynchronous version of GetSchema(). Providers should override with an appropriate implementation. The `cancellationToken` can optionally be honored. The default implementation invokes the synchronous GetSchema() call and returns a completed task. The default implementation will return a cancelled task if passed an already cancelled `cancellationToken`. Exceptions thrown by GetSchema() will be communicated via the returned Task Exception property. (Inherited from DbConnection)
GetSchemaAsync(String, CancellationToken)	This is the asynchronous version of GetSchema(String). Providers should override with an appropriate implementation. The `cancellationToken` can optionally be honored. The default implementation invokes the synchronous GetSchema(String) call and returns a completed task. The default implementation will return a cancelled task if passed an already cancelled `cancellationToken`. Exceptions thrown by GetSchema(String) will be communicated via the returned Task Exception property. (Inherited from DbConnection)
GetSchemaAsync(String, String[], CancellationToken)	This is the asynchronous version of GetSchema(String, String[]). Providers should override with an appropriate implementation. The `cancellationToken` can optionally be honored. The default implementation invokes the synchronous GetSchema(String, String[]) call and returns a completed task. The default implementation will return a cancelled task if passed an already cancelled `cancellationToken`. Exceptions thrown by GetSchema(String, String[]) will be communicated via the returned Task Exception property. (Inherited from DbConnection)
GetService(Type)	Returns an object that represents a service provided by the Component or by its Container. (Inherited from Component)
GetType()	Gets the Type of the current instance. (Inherited from Object)
InitializeLifetimeService()	Obsolete. Obtains a lifetime service object to control the lifetime policy for this instance. (Inherited from MarshalByRefObject)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
MemberwiseClone(Boolean)	Creates a shallow copy of the current MarshalByRefObject object. (Inherited from MarshalByRefObject)
OnStateChange(StateChangeEventArgs)	Raises the StateChange event. (Inherited from DbConnection)
Open()	Establishes a connection to the data source by calling the underlying data provider's `Open` method.
OpenAsync()	An asynchronous version of Open(), which opens a database connection with the settings specified by the ConnectionString. This method invokes the virtual method OpenAsync(CancellationToken) with CancellationToken.None. (Inherited from DbConnection)
OpenAsync(CancellationToken)	This is the asynchronous version of Open(). Providers should override with an appropriate implementation. The cancellation token can optionally be honored. The default implementation invokes the synchronous Open() call and returns a completed task. The default implementation will return a cancelled task if passed an already cancelled cancellationToken. Exceptions thrown by Open will be communicated via the returned Task Exception property. Do not invoke other methods and properties of the `DbConnection` object until the returned Task is complete. (Inherited from DbConnection)
ToString()	Returns a String containing the name of the Component, if any. This method should not be overridden. (Inherited from Component)

Events

Disposed	Occurs when the component is disposed by a call to the Dispose() method. (Inherited from Component)
StateChange	Occurs when the state of the connection changes. (Inherited from DbConnection)

Explicit Interface Implementations

IDbConnection.BeginTransaction()	Begins a database transaction. (Inherited from DbConnection)
IDbConnection.BeginTransaction(IsolationLevel)	Begins a database transaction with the specified isolation level. (Inherited from DbConnection)
IDbConnection.CreateCommand()	Creates and returns a DbCommand object that is associated with the current connection. (Inherited from DbConnection)

Applies to

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