GetChars Method

OdbcDataReader.GetChars Method (Int32, Int64, Char[], Int32, Int32)


Reads a stream of characters from the specified column offset into the buffer as an array, starting at the particular buffer offset.

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

public override long GetChars(
	int i,
	long dataIndex,
	char[] buffer,
	int bufferIndex,
	int length


Type: System.Int32

The zero-based column ordinal.

Type: System.Int64

The index within the row where the read operation is to start.

Type: System.Char[]

The buffer into which to copy data.

Type: System.Int32

The index within the buffer where the write operation is to start.

Type: System.Int32

The number of characters to read.

Return Value

Type: System.Int64

The actual number of characters read.

GetChars returns the number of available characters in the field. Most of the time this is the exact length of the field. However, the number returned may be less than the true length of the field if GetChars has already been used to obtain characters from the field. This may be the case, for example, if the OdbcDataReader is reading a large data structure into a buffer. For more information, see the SequentialAccess setting for CommandBehavior.

If you pass a buffer that is a null value, GetChars returns the length of the field in characters.

Conversions are performed based on the underlying capabilities of the ODBC driver. If the conversion is not supported then the method call will fail.


No exception will be thrown if the value of bufferIndex is outside the array. No data will be read and the method will return 0.

.NET Framework
Available since 1.1
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