UltraLite for MobileVB User's Guide
UltraLite for MobileVB API Reference
ULResultSet class
GetByteChunk ( _
index As Integer, _
src_offset As Long, _
data As Long, _
data_len As Long, _
filled_len As Long _
) As Boolean
Member of UltraLiteAFLib.ULResultSet
Fills the buffer passed in (which should be an array) with the binary data in the column. Suitable for BLOBS.
index The 1-based ordinal of the column containing the binary data.
offset The offset into the underlying array of bytes. The source offset must be greater than or equal to 0, otherwise a SQLE_INVALID_PARAMETER error will be raised. A buffer bigger than 64K is also permissible.
data A pointer to an array of bytes. To get the pointer to the array of bytes, use the Visual Basic VarPtr() function.
data_len The length of the buffer, or array. The data_len must be greater than or equal to 0.
filled_len The number of bytes fetched. Because you don't know how big the BLOB data is in advance, you generally fetch it using a fixed-length chunk, one chunk at a time. The last chunk may be smaller than your chunk size. filled_len reports how many bytes were actually fetched.
The number of bytes read.
| Error | Description |
|---|---|
| ulSQLE_CONVERSION_ERROR | The error occurs if the column data type is not BINARY or LONG BINARY |
| ulSQLE_INVALID_PARAMETER |
The error occurs if the column data type is BINARY and the offset is not 0 or 1, or, the data length is less than 0.
The error also occurs if the column data type is LONG BINARY and the offset is less than 1. |
In the following example, edata is a column name. If the data_len parameter passed in is not sufficiently long, the entire application will terminate.
Dim data (512) As Byte
...
table.Column("edata").GetByteChunk(0,data)