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

  • Reference

Definition

Namespace:
System.Data.Odbc
Assembly:
System.Data.Odbc.dll
Assembly:
System.Data.dll
Package:
System.Data.Odbc v9.0.0
Source:
OdbcDataReader.cs
Source:
OdbcDataReader.cs
Source:
OdbcDataReader.cs

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

public:
 override long GetChars(int i, long dataIndex, cli::array <char> ^ buffer, int bufferIndex, int length);
public:
 virtual long GetChars(int i, long dataIndex, cli::array <char> ^ buffer, int bufferIndex, int length);
public override long GetChars (int i, long dataIndex, char[]? buffer, int bufferIndex, int length);
public long GetChars (int i, long dataIndex, char[] buffer, int bufferIndex, int length);
public override long GetChars (int i, long dataIndex, char[] buffer, int bufferIndex, int length);
override this.GetChars : int * int64 * char[] * int * int -> int64
abstract member GetChars : int * int64 * char[] * int * int -> int64
override this.GetChars : int * int64 * char[] * int * int -> int64
Public Overrides Function GetChars (i As Integer, dataIndex As Long, buffer As Char(), bufferIndex As Integer, length As Integer) As Long
Public Function GetChars (i As Integer, dataIndex As Long, buffer As Char(), bufferIndex As Integer, length As Integer) As Long

Parameters

i
Int32

The zero-based column ordinal.

dataIndex
Int64

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

buffer
Char[]

The buffer into which to copy data.

bufferIndex
Int32

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

length
Int32

The number of characters to read.

Returns

Int64

The actual number of characters read.

Implements

GetChars(Int32, Int64, Char[], Int32, Int32)

Remarks

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.

Note

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.

Applies to

See also