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SqlDataReader.GetTextReader(Int32) Method

  • Reference

Definition

Namespace:
System.Data.SqlClient
Assembly:
System.Data.SqlClient.dll
Assembly:
System.Data.dll
Package:
System.Data.SqlClient v4.9.0
Source:
System.Data.SqlClient.notsupported.cs

Retrieves Char, NChar, NText, NVarChar, text, varChar, and Variant data types as a TextReader.

public:
 override System::IO::TextReader ^ GetTextReader(int i);
public override System.IO.TextReader GetTextReader (int i);
override this.GetTextReader : int -> System.IO.TextReader
Public Overrides Function GetTextReader (i As Integer) As TextReader

Parameters

i
Int32

The column to be retrieved.

Returns

TextReader

The returned 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.

InvalidCastException

The returned type was not one of the types below:

  • char

  • nchar

  • ntext

  • nvarchar

  • text

  • varchar

Remarks

SqlException exceptions raised from TextReader are thrown as IOException exceptions; check the inner exception for the SqlException.

Null values will be returned as an empty (zero bytes) TextReader.

GetChars will raise an InvalidOperationException exception when used on an object returned by GetTextReader when SequentialAccess is in effect.

When the connection property ContextConnection=true, GetTextReader only supports synchronous data retrieval for both sequential (SequentialAccess) and non-sequential (Default) access.

For more information, see SqlClient Streaming Support.

Applies to