SqlCommand.ExecuteReaderAsync Method
Definition
Important
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Overloads
| ExecuteReaderAsync() |
An asynchronous version of ExecuteReader() , which sends the CommandText to the Connection and builds a SqlDataReader . Exceptions will be reported via the returned Task object. |
| ExecuteReaderAsync(CommandBehavior) |
An asynchronous version of ExecuteReader(CommandBehavior) , which sends the CommandText to the Connection , and builds a SqlDataReader . Exceptions will be reported via the returned Task object. |
| ExecuteReaderAsync(CancellationToken) |
An asynchronous version of ExecuteReader() , which sends the CommandText to the Connection and builds a SqlDataReader . The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object. |
| ExecuteReaderAsync(CommandBehavior, CancellationToken) |
An asynchronous version of ExecuteReader(CommandBehavior) , which sends the CommandText to the Connection , and builds a SqlDataReader The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object. |
ExecuteReaderAsync()
An asynchronous version of ExecuteReader() , which sends the CommandText to the Connection and builds a SqlDataReader . Exceptions will be reported via the returned Task object.
public:
System::Threading::Tasks::Task<Microsoft::Data::SqlClient::SqlDataReader ^> ^ ExecuteReaderAsync();public System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader> ExecuteReaderAsync ();override this.ExecuteReaderAsync : unit -> System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader>Public Function ExecuteReaderAsync () As Task(Of SqlDataReader)Returns
A task representing the asynchronous operation.
Exceptions
A SqlDbType other than Binary or VarBinary was used when Value was set to Stream . For more information about streaming, see SqlClient Streaming Support.
-or-
A SqlDbType other than Char, NChar, NVarChar, VarChar, or Xml was used when Value was set to TextReader .
-or-
A SqlDbType other than Xml was used when Value was set to XmlReader .
An invalid CommandBehavior value.
Calling ExecuteReaderAsync() more than once for the same instance before task completion.
-or-
The SqlConnection closed or dropped during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
SQL Server returned an error while executing the command text.
-or-
A timeout occurred during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
An error occurred in a Stream , XmlReader or TextReader object during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
The Stream , XmlReader or TextReader object was closed during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
Remarks
For more information about asynchronous programming in the .NET Framework Data Provider for SQL Server, see Asynchronous Programming.
Note
For long running queries on the server, consider using ExecuteReader due to a known issue with canceling queries via a cancellation token. Also, consider canceling execution using the Cancel method.
Applies to
ExecuteReaderAsync(CommandBehavior)
An asynchronous version of ExecuteReader(CommandBehavior) , which sends the CommandText to the Connection , and builds a SqlDataReader . Exceptions will be reported via the returned Task object.
public:
System::Threading::Tasks::Task<Microsoft::Data::SqlClient::SqlDataReader ^> ^ ExecuteReaderAsync(System::Data::CommandBehavior behavior);public System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader> ExecuteReaderAsync (System.Data.CommandBehavior behavior);override this.ExecuteReaderAsync : System.Data.CommandBehavior -> System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader>Public Function ExecuteReaderAsync (behavior As CommandBehavior) As Task(Of SqlDataReader)Parameters
- behavior
- CommandBehavior
Options for statement execution and data retrieval. When is set to
Default
,
ReadAsync(CancellationToken)
reads the entire row before returning a complete Task.
Returns
A task representing the asynchronous operation.
Exceptions
A SqlDbType other than Binary or VarBinary was used when Value was set to Stream . For more information about streaming, see SqlClient Streaming Support.
-or-
A SqlDbType other than Char, NChar, NVarChar, VarChar, or Xml was used when Value was set to TextReader .
-or-
A SqlDbType other than Xml was used when Value was set to XmlReader .
An invalid CommandBehavior value.
Calling ExecuteReaderAsync(CommandBehavior) more than once for the same instance before task completion.
-or- SqlConnection closed or dropped during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
SQL Server returned an error while executing the command text.
-or-
A timeout occurred during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
An error occurred in a Stream , XmlReader or TextReader object during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
The Stream , XmlReader or TextReader object was closed during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
Remarks
For more information about asynchronous programming in the .NET Framework Data Provider for SQL Server, see Asynchronous Programming.
Applies to
ExecuteReaderAsync(CancellationToken)
An asynchronous version of ExecuteReader() , which sends the CommandText to the Connection and builds a SqlDataReader .
The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object.
public:
System::Threading::Tasks::Task<Microsoft::Data::SqlClient::SqlDataReader ^> ^ ExecuteReaderAsync(System::Threading::CancellationToken cancellationToken);public System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader> ExecuteReaderAsync (System.Threading.CancellationToken cancellationToken);override this.ExecuteReaderAsync : System.Threading.CancellationToken -> System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader>Public Function ExecuteReaderAsync (cancellationToken As CancellationToken) As Task(Of SqlDataReader)Parameters
- cancellationToken
- CancellationToken
The cancellation instruction.
Returns
A task representing the asynchronous operation.
Exceptions
A SqlDbType other than Binary or VarBinary was used when Value was set to Stream . For more information about streaming, see SqlClient Streaming Support.
-or-
A SqlDbType other than Char, NChar, NVarChar, VarChar, or Xml was used when Value was set to TextReader .
-or-
A SqlDbType other than Xml was used when Value was set to XmlReader .
An invalid CommandBehavior value.
Calling ExecuteReaderAsync(CommandBehavior, CancellationToken) more than once for the same instance before task completion.
-or-
The SqlConnection closed or dropped during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
SQL Server returned an error while executing the command text.
-or-
A timeout occurred during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
An error occurred in a Stream , XmlReader or TextReader object during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
The Stream , XmlReader or TextReader object was closed during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
Remarks
For more information about asynchronous programming in the .NET Framework Data Provider for SQL Server, see Asynchronous Programming.
Applies to
ExecuteReaderAsync(CommandBehavior, CancellationToken)
An asynchronous version of ExecuteReader(CommandBehavior) , which sends the CommandText to the Connection , and builds a SqlDataReader The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object.
public:
System::Threading::Tasks::Task<Microsoft::Data::SqlClient::SqlDataReader ^> ^ ExecuteReaderAsync(System::Data::CommandBehavior behavior, System::Threading::CancellationToken cancellationToken);public System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader> ExecuteReaderAsync (System.Data.CommandBehavior behavior, System.Threading.CancellationToken cancellationToken);override this.ExecuteReaderAsync : System.Data.CommandBehavior * System.Threading.CancellationToken -> System.Threading.Tasks.Task<Microsoft.Data.SqlClient.SqlDataReader>Public Function ExecuteReaderAsync (behavior As CommandBehavior, cancellationToken As CancellationToken) As Task(Of SqlDataReader)Parameters
- behavior
- CommandBehavior
Options for statement execution and data retrieval. When is set to
Default
,
ReadAsync(CancellationToken)
reads the entire row before returning a complete Task.
- cancellationToken
- CancellationToken
The cancellation instruction.
Returns
A task representing the asynchronous operation.
Exceptions
A SqlDbType other than Binary or VarBinary was used when Value was set to Stream . For more information about streaming, see SqlClient Streaming Support.
-or-
A SqlDbType other than Char, NChar, NVarChar, VarChar, or Xml was used when Value was set to TextReader .
-or-
A SqlDbType other than Xml was used when Value was set to XmlReader .
An invalid CommandBehavior value.
Calling ExecuteReaderAsync(CommandBehavior, CancellationToken) more than once for the same instance before task completion.
-or-
The SqlConnection closed or dropped during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
SQL Server returned an error while executing the command text.
-or-
A timeout occurred during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
An error occurred in a Stream , XmlReader or TextReader object during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
The Stream , XmlReader or TextReader object was closed during a streaming operation. For more information about streaming, see SqlClient Streaming Support.
Remarks
For more information about asynchronous programming in the .NET Framework Data Provider for SQL Server, see Asynchronous Programming.