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SqlCommand.ExecuteXmlReaderAsync Method

Definition

Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand and returns results as an XmlReader object.

Overloads

ExecuteXmlReaderAsync()

An asynchronous version of ExecuteXmlReader(), which sends the CommandText to the Connection and builds an XmlReader object.

Exceptions will be reported via the returned Task object.

ExecuteXmlReaderAsync(CancellationToken)

An asynchronous version of ExecuteXmlReader(), which sends the CommandText to the Connection and builds an XmlReader object.

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.

ExecuteXmlReaderAsync()

An asynchronous version of ExecuteXmlReader(), which sends the CommandText to the Connection and builds an XmlReader object.

Exceptions will be reported via the returned Task object.

public:
 System::Threading::Tasks::Task<System::Xml::XmlReader ^> ^ ExecuteXmlReaderAsync();
public System.Threading.Tasks.Task<System.Xml.XmlReader> ExecuteXmlReaderAsync ();
member this.ExecuteXmlReaderAsync : unit -> System.Threading.Tasks.Task<System.Xml.XmlReader>
Public Function ExecuteXmlReaderAsync () As Task(Of XmlReader)

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.

Calling ExecuteScalarAsync(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.

-or-

Context Connection=true is specified in the connection string.

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

The XmlReader returned by this method does not support asynchronous operations.

For more information about asynchronous programming in the .NET Framework Data Provider for SQL Server, see Asynchronous Programming.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such as ArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown by ExecuteXmlReader().

See also

Applies to

ExecuteXmlReaderAsync(CancellationToken)

An asynchronous version of ExecuteXmlReader(), which sends the CommandText to the Connection and builds an XmlReader object.

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<System::Xml::XmlReader ^> ^ ExecuteXmlReaderAsync(System::Threading::CancellationToken cancellationToken);
public System.Threading.Tasks.Task<System.Xml.XmlReader> ExecuteXmlReaderAsync (System.Threading.CancellationToken cancellationToken);
member this.ExecuteXmlReaderAsync : System.Threading.CancellationToken -> System.Threading.Tasks.Task<System.Xml.XmlReader>
Public Function ExecuteXmlReaderAsync (cancellationToken As CancellationToken) As Task(Of XmlReader)

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.

Calling ExecuteScalarAsync(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.

-or-

Context Connection=true is specified in the connection string.

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.

The cancellation token was canceled. This exception is stored into the returned task.

Remarks

The XmlReader returned by this method does not support asynchronous operations.

For more information about asynchronous programming in the .NET Framework Data Provider for SQL Server, see Asynchronous Programming.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such as ArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown by ExecuteXmlReader().

See also

Applies to