SqlDataReader.GetFieldValueAsync<T>(Int32, CancellationToken) Method

  • Reference

Definition

Namespace:
Microsoft.Data.SqlClient
Assembly:
Microsoft.Data.SqlClient.dll
Package:
Microsoft.Data.SqlClient v1.0.19269.1
Package:
Microsoft.Data.SqlClient v1.1.4
Package:
Microsoft.Data.SqlClient v2.0.1
Package:
Microsoft.Data.SqlClient v2.1.4
Package:
Microsoft.Data.SqlClient v3.0.1
Package:
Microsoft.Data.SqlClient v3.1.0
Package:
Microsoft.Data.SqlClient v4.0.1
Package:
Microsoft.Data.SqlClient v4.1.0
Package:
Microsoft.Data.SqlClient v5.0.0
Package:
Microsoft.Data.SqlClient v5.1.0
Package:
Microsoft.Data.SqlClient v5.2.0

Asynchronously gets the value of the specified column as a type. GetFieldValue<T>(Int32) is the synchronous version of this method.

public:
generic <typename T>
 override System::Threading::Tasks::Task<T> ^ GetFieldValueAsync(int i, System::Threading::CancellationToken cancellationToken);
public override System.Threading.Tasks.Task<T> GetFieldValueAsync<T> (int i, System.Threading.CancellationToken cancellationToken);
override this.GetFieldValueAsync : int * System.Threading.CancellationToken -> System.Threading.Tasks.Task<'T>
Public Overrides Function GetFieldValueAsync(Of T) (i As Integer, cancellationToken As CancellationToken) As Task(Of T)

Type Parameters

T

The type of the value to be returned.

Parameters

i
Int32

The column to be retrieved.

cancellationToken
CancellationToken

The cancellation instruction, which propagates a notification that operations should be canceled. This does not guarantee the cancellation. A setting of CancellationToken.None makes this method equivalent to IsDBNull(Int32). The returned task must be marked as cancelled.

Returns

Task<T>

The returned type object.

Exceptions

InvalidOperationException

The connection drops or is closed during the data retrieval.

The SqlDataReader is closed during the data retrieval.

There is no data ready to be read (for example, the first Read() hasn't been called, or returned false).

Tried to read a previously-read column in sequential mode.

There was an asynchronous operation in progress. This applies to all Get* methods when running in sequential mode, as they could be called while reading a stream.

IndexOutOfRangeException

Trying to read a column that does not exist.

SqlNullValueException

The value of the column was null (IsDBNull(Int32) == true), retrieving a non-SQL type.

InvalidCastException

T doesn't match the type returned by SQL Server or cannot be cast.

Remarks

T can be one of the following types:
Boolean Byte Char DateOnly (.NET 6 or later)
DateTime DateTimeOffset Decimal Double
Float Guid Int16 Int32
Int64 SqlBoolean SqlByte SqlDateTime
SqlDecimal SqlDouble SqlGuid SqlInt16
SqlInt32 SqlInt64 SqlMoney SqlSingle
SqlString Stream String TextReader
TimeOnly (.NET 6 or later) XmlReader UDT, which can be any CLR type marked with SqlUserDefinedTypeAttribute.

For more information, see SqlClient Streaming Support.

Applies to