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DbCommand Class

Definition

Represents an SQL statement or stored procedure to execute against a data source. Provides a base class for database-specific classes that represent commands. ExecuteNonQueryAsync.

public ref class DbCommand abstract : IDisposable
public ref class DbCommand abstract : System::ComponentModel::Component, IAsyncDisposable, IDisposable, System::Data::IDbCommand
public ref class DbCommand abstract : IDisposable, System::Data::IDbCommand
public ref class DbCommand abstract : System::ComponentModel::Component, IDisposable, System::Data::IDbCommand
public ref class DbCommand abstract : System::ComponentModel::Component, System::Data::IDbCommand
public ref class DbCommand abstract : System::ComponentModel::Component, IAsyncDisposable, System::Data::IDbCommand
public abstract class DbCommand : IDisposable
public abstract class DbCommand : System.ComponentModel.Component, IAsyncDisposable, IDisposable, System.Data.IDbCommand
public abstract class DbCommand : IDisposable, System.Data.IDbCommand
public abstract class DbCommand : System.ComponentModel.Component, IDisposable, System.Data.IDbCommand
public abstract class DbCommand : System.ComponentModel.Component, System.Data.IDbCommand
public abstract class DbCommand : System.ComponentModel.Component, IAsyncDisposable, System.Data.IDbCommand
type DbCommand = class
    interface IDisposable
type DbCommand = class
    inherit Component
    interface IDbCommand
    interface IDisposable
    interface IAsyncDisposable
type DbCommand = class
    interface IDbCommand
    interface IDisposable
type DbCommand = class
    inherit Component
    interface IDbCommand
    interface IDisposable
Public MustInherit Class DbCommand
Implements IDisposable
Public MustInherit Class DbCommand
Inherits Component
Implements IAsyncDisposable, IDbCommand, IDisposable
Public MustInherit Class DbCommand
Implements IDbCommand, IDisposable
Public MustInherit Class DbCommand
Inherits Component
Implements IDbCommand, IDisposable
Public MustInherit Class DbCommand
Inherits Component
Implements IDbCommand
Public MustInherit Class DbCommand
Inherits Component
Implements IAsyncDisposable, IDbCommand
Inheritance
DbCommand
Inheritance
Derived
Implements

Constructors

DbCommand()

Constructs an instance of the DbCommand object.

Properties

CanRaiseEvents

Gets a value indicating whether the component can raise an event.

(Inherited from Component)
CommandText

Gets or sets the text command to run against the data source.

CommandTimeout

Gets or sets the wait time (in seconds) before terminating the attempt to execute the command and generating an error.

CommandType

Gets or sets how the CommandText property is interpreted.

Connection

Gets or sets the DbConnection used by this DbCommand.

Container

Gets the IContainer that contains the Component.

(Inherited from Component)
DbConnection

Gets or sets the DbConnection used by this DbCommand.

DbParameterCollection

Gets the collection of DbParameter objects.

DbTransaction

Gets or sets the DbTransaction within which this DbCommand object executes.

DesignMode

Gets a value that indicates whether the Component is currently in design mode.

(Inherited from Component)
DesignTimeVisible

Gets or sets a value indicating whether the command object should be visible in a customized interface control.

Events

Gets the list of event handlers that are attached to this Component.

(Inherited from Component)
Parameters

Gets the collection of DbParameter objects. For more information on parameters, see Configuring Parameters and Parameter Data Types.

Site

Gets or sets the ISite of the Component.

(Inherited from Component)
Transaction

Gets or sets the DbTransaction within which this DbCommand object executes.

UpdatedRowSource

Gets or sets how command results are applied to the DataRow when used by the Update method of a DbDataAdapter.

Methods

Cancel()

Attempts to cancel the execution of a DbCommand.

CreateDbParameter()

Creates a new instance of a DbParameter object.

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)
CreateParameter()

Creates a new instance of a DbParameter object.

Dispose()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.

Dispose()

Releases all resources used by the Component.

(Inherited from Component)
Dispose(Boolean)

Releases the unmanaged resources used by the DbCommand and optionally releases the managed resources.

Dispose(Boolean)

Releases the unmanaged resources used by the Component and optionally releases the managed resources.

(Inherited from Component)
DisposeAsync()

Asynchronously diposes the command object.

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
ExecuteDbDataReader(CommandBehavior)

Executes the command against its connection, returning a DbDataReader which can be used to access the results.

ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken)

Providers should implement this method to provide a non-default implementation for ExecuteReader overloads.

The default implementation invokes the synchronous ExecuteReader() method and returns a completed task, blocking the calling thread. The default implementation will return a cancelled task if passed an already cancelled cancellation token. Exceptions thrown by ExecuteReader will be communicated via the returned Task Exception property.

This method accepts a cancellation token that can be used to request the operation to be cancelled early. Implementations may ignore this request.

ExecuteNonQuery()

Executes the command against its connection object, returning the number of rows affected.

ExecuteNonQueryAsync()

An asynchronous version of ExecuteNonQuery(), which executes the command against its connection object, returning the number of rows affected.

Invokes ExecuteNonQueryAsync(CancellationToken) with CancellationToken.None.

ExecuteNonQueryAsync(CancellationToken)

This is the asynchronous version of ExecuteNonQuery(). Providers should override with an appropriate implementation. The cancellation token may optionally be ignored.

The default implementation invokes the synchronous ExecuteNonQuery() method and returns a completed task, blocking the calling thread. The default implementation will return a cancelled task if passed an already cancelled cancellation token. Exceptions thrown by ExecuteNonQuery() will be communicated via the returned Task Exception property.

Do not invoke other methods and properties of the DbCommand object until the returned Task is complete.

ExecuteReader()

Executes the command against its connection, returning a DbDataReader which can be used to access the results.

ExecuteReader(CommandBehavior)

Executes the command against its connection, returning a DbDataReader which can be used to access the results.

ExecuteReaderAsync()

An asynchronous version of ExecuteReader, which executes the command against its connection, returning a DbDataReader which can be used to access the results.

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken) with CancellationToken.None.

ExecuteReaderAsync(CancellationToken)

An asynchronous version of ExecuteReader, which executes the command against its connection, returning a DbDataReader which can be used to access the results.

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken).

ExecuteReaderAsync(CommandBehavior, CancellationToken)

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken).

ExecuteReaderAsync(CommandBehavior)

An asynchronous version of ExecuteReader, which executes the command against its connection, returning a DbDataReader which can be used to access the results.

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken).

ExecuteScalar()

Executes the command and returns the first column of the first row in the first returned result set. All other columns, rows and result sets are ignored.

ExecuteScalarAsync()

An asynchronous version of ExecuteScalar(), which executes the command and returns the first column of the first row in the first returned result set. All other columns, rows and result sets are ignored.

Invokes ExecuteScalarAsync(CancellationToken) with CancellationToken.None.

ExecuteScalarAsync(CancellationToken)

This is the asynchronous version of ExecuteScalar(). Providers should override with an appropriate implementation. The cancellation token may optionally be ignored.

The default implementation invokes the synchronous ExecuteScalar() method and returns a completed task, blocking the calling thread. The default implementation will return a cancelled task if passed an already cancelled cancellation token. Exceptions thrown by ExecuteScalar will be communicated via the returned Task Exception property.

Do not invoke other methods and properties of the DbCommand object until the returned Task is complete.

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)
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)
Prepare()

Creates a prepared (or compiled) version of the command on the data source.

PrepareAsync(CancellationToken)

Asynchronously creates a prepared (or compiled) version of the command on the data source.

ToString()

Returns a string that represents the current object.

(Inherited from Object)
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)

Explicit Interface Implementations

IDbCommand.Connection

Gets or sets the IDbConnection used by this instance of the IDbCommand.

IDbCommand.CreateParameter()

Creates a new instance of an IDbDataParameter object.

IDbCommand.ExecuteReader()

Executes the CommandText against the Connection and builds an IDataReader.

IDbCommand.ExecuteReader(CommandBehavior)

Executes the CommandText against the Connection, and builds an IDataReader using one of the CommandBehavior values.

IDbCommand.Parameters

Gets the IDataParameterCollection.

IDbCommand.Transaction

Gets or sets the DbTransaction within which this DbCommand object executes.

Extension Methods

ConfigureAwait(IAsyncDisposable, Boolean)

Configures how awaits on the tasks returned from an async disposable will be performed.

Applies to

See also