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OleDbDataReader Class

Provides a way of reading a forward-only stream of data rows from a data source. This class cannot be inherited.

Namespace:  System.Data.OleDb
Assembly:  System.Data (in System.Data.dll)

'Declaration
Public NotInheritable Class OleDbDataReader _
	Inherits DbDataReader

The OleDbDataReader type exposes the following members.

  NameDescription
Public propertyDepthGets a value that indicates the depth of nesting for the current row. (Overrides DbDataReader.Depth.)
Public propertyFieldCountGets the number of columns in the current row. (Overrides DbDataReader.FieldCount.)
Public propertyHasRowsGets a value that indicates whether the OleDbDataReader contains one or more rows. (Overrides DbDataReader.HasRows.)
Public propertyIsClosedIndicates whether the data reader is closed. (Overrides DbDataReader.IsClosed.)
Public propertyItem(Int32)Gets the value of the specified column in its native format given the column ordinal. (Overrides DbDataReader.Item(Int32).)
Public propertyItem(String)Gets the value of the specified column in its native format given the column name. (Overrides DbDataReader.Item(String).)
Public propertyRecordsAffectedGets the number of rows changed, inserted, or deleted by execution of the SQL statement. (Overrides DbDataReader.RecordsAffected.)
Public propertyVisibleFieldCountGets the number of fields in the OleDbDataReader that are not hidden. (Overrides DbDataReader.VisibleFieldCount.)
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  NameDescription
Public methodCloseCloses the OleDbDataReader object. (Overrides DbDataReader.Close.)
Public methodCreateObjRefCreates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object. (Inherited from MarshalByRefObject.)
Public methodDisposeReleases all resources used by the current instance of the DbDataReader class. (Inherited from DbDataReader.)
Protected methodDispose(Boolean)Releases the managed resources used by the DbDataReader and optionally releases the unmanaged resources. (Inherited from DbDataReader.)
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetBooleanGets the value of the specified column as a Boolean. (Overrides DbDataReader.GetBoolean(Int32).)
Public methodGetByteGets the value of the specified column as a byte. (Overrides DbDataReader.GetByte(Int32).)
Public methodGetBytesReads a stream of bytes from the specified column offset into the buffer as an array starting at the given buffer offset. (Overrides DbDataReader.GetBytes(Int32, Int64, Byte(), Int32, Int32).)
Public methodGetCharGets the value of the specified column as a character. (Overrides DbDataReader.GetChar(Int32).)
Public methodGetCharsReads a stream of characters from the specified column offset into the buffer as an array starting at the given buffer offset. (Overrides DbDataReader.GetChars(Int32, Int64, Char(), Int32, Int32).)
Public methodGetDataReturns an OleDbDataReader object for the requested column ordinal.
Public methodGetDataTypeNameGets the name of the source data type. (Overrides DbDataReader.GetDataTypeName(Int32).)
Public methodGetDateTimeGets the value of the specified column as a DateTime object. (Overrides DbDataReader.GetDateTime(Int32).)
Protected methodGetDbDataReaderReturns a DbDataReader object for the requested column ordinal that can be overridden with a provider-specific implementation. (Inherited from DbDataReader.)
Public methodGetDecimalGets the value of the specified column as a Decimal object. (Overrides DbDataReader.GetDecimal(Int32).)
Public methodGetDoubleGets the value of the specified column as a double-precision floating-point number. (Overrides DbDataReader.GetDouble(Int32).)
Public methodGetEnumeratorReturns an IEnumerator that can be used to iterate through the rows in the data reader. (Overrides DbDataReader.GetEnumerator.)
Public methodGetFieldTypeGets the Type that is the data type of the object. (Overrides DbDataReader.GetFieldType(Int32).)
Public methodGetFloatGets the value of the specified column as a single-precision floating-point number. (Overrides DbDataReader.GetFloat(Int32).)
Public methodGetGuidGets the value of the specified column as a globally unique identifier (GUID). (Overrides DbDataReader.GetGuid(Int32).)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetInt16Gets the value of the specified column as a 16-bit signed integer. (Overrides DbDataReader.GetInt16(Int32).)
Public methodGetInt32Gets the value of the specified column as a 32-bit signed integer. (Overrides DbDataReader.GetInt32(Int32).)
Public methodGetInt64Gets the value of the specified column as a 64-bit signed integer. (Overrides DbDataReader.GetInt64(Int32).)
Public methodGetLifetimeServiceRetrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject.)
Public methodGetNameGets the name of the specified column. (Overrides DbDataReader.GetName(Int32).)
Public methodGetOrdinalGets the column ordinal, given the name of the column. (Overrides DbDataReader.GetOrdinal(String).)
Public methodGetProviderSpecificFieldTypeReturns the provider-specific field type of the specified column. (Inherited from DbDataReader.)
Public methodGetProviderSpecificValueGets the value of the specified column as an instance of Object. (Inherited from DbDataReader.)
Public methodGetProviderSpecificValuesGets all provider-specific attribute columns in the collection for the current row. (Inherited from DbDataReader.)
Public methodGetSchemaTableReturns a DataTable that describes the column metadata of the OleDbDataReader. (Overrides DbDataReader.GetSchemaTable.)
Public methodGetStringGets the value of the specified column as a string. (Overrides DbDataReader.GetString(Int32).)
Public methodGetTimeSpanGets the value of the specified column as a TimeSpan object.
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodGetValueGets the value of the column at the specified ordinal in its native format. (Overrides DbDataReader.GetValue(Int32).)
Public methodGetValuesPopulates an array of objects with the column values of the current row. (Overrides DbDataReader.GetValues(Object()).)
Public methodInitializeLifetimeServiceObtains a lifetime service object to control the lifetime policy for this instance. (Inherited from MarshalByRefObject.)
Public methodIsDBNullGets a value that indicates whether the column contains nonexistent or missing values. (Overrides DbDataReader.IsDBNull(Int32).)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Protected methodMemberwiseClone(Boolean)Creates a shallow copy of the current MarshalByRefObject object. (Inherited from MarshalByRefObject.)
Public methodNextResultAdvances the data reader to the next result, when reading the results of batch SQL statements. (Overrides DbDataReader.NextResult.)
Public methodReadAdvances the OleDbDataReader to the next record. (Overrides DbDataReader.Read.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
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  NameDescription
Explicit interface implemetationPrivate methodIDataRecord.GetDataFor a description of this member, see IDataRecord.GetData. (Inherited from DbDataReader.)
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To create an OleDbDataReader, you must call the ExecuteReader method of the OleDbCommand object, instead of directly using a constructor.

Before you close the OleDbConnection, first close the OleDbDataReader object. You must also close the OleDbDataReader object if you plan to resuse an OleDbCommand object.For example, you cannot retrieve output parameters until after you call Close.

Changes made to a result set by another process or thread while data is being read may be visible to the user of the OleDbDataReader. However, the precise behavior is timing dependent.

IsClosed and RecordsAffected are the only properties that you can call after the OleDbDataReader is closed. Although the RecordsAffected property may be accessed while the OleDbDataReader exists, always call Close before returning the value of RecordsAffected to guarantee an accurate return value.

The following example creates an OleDbConnection, an OleDbCommand, and an OleDbDataReader. The example reads through the data, writing it out to the console. Finally, the example closes the OleDbDataReader and then the OleDbConnection.


Public Sub ReadData(ByVal connectionString As String, _
    ByVal queryString As String)
    Using connection As New OleDbConnection(connectionString)
        Dim command As New OleDbCommand(queryString, connection)

        connection.Open()

        Dim reader As OleDbDataReader = command.ExecuteReader()
        While reader.Read()
            Console.WriteLine(reader(0).ToString())
        End While
        reader.Close()
    End Using
End Sub


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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