HB_Recordset

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The HB_Recordset class implements the necessary methods to manipulate the content of Palm databases the structure of which matches a HB++ table. Since a mapping has to be established between the record data and the fields of the table, it is necessary to specify the structure of the table corresponding to the.pdb when opening it. It is done by providing a path to the.hbx file, or a Table Digest.

At any moment, only one record is accessible through the HB_Recordset object. A cursor is used to determine which record is active, and to navigate through all the records. This cursor is managed by the AbsolutePosition, MoveFirst, MoveLast, MoveNext and MovePrevious methods. The BOF and EOF properties are used to determine if the cursor is positioned before the first record or after the last one. You can use these indicators to exit a loop which steps through all the records, for example.

If the table is open for writing, the AddNew method adds a new record, while the Edit method switches the HB_Recordset object to edit mode. You can then modify the value of the fields, and the Update method validates these modifications.

It is not advised to create several HB_Recordset objects accessing the same.pdb file at the same time. When a recordset is no longer needed, it should be closed with the Close method.

Members	Description

AbsolutePosition	Absolute position of the current record within the table.
AddNew	Adds a new record.
AppInfoBlock	Retrieves or modify the content of the application info block.
Blank	Empties the contents of a record.
BOF	Indicates whether the cursor is positioned before the first record in the recordset.
CancelUpdate	Cancels the modifications carried out on the current record.
Close	Closes the Palm database currently opened.
CreateHBBitmap	Convert an OLE picture into a HB++ bitmap stored in a byte array.
CreateOlePicture	Convert a HB++ bitmap in a byte array to a standard OLE picture object.
CreateTable	Creates and opens an empty Palm database and.pdb file.
Delete	Deletes the record on which the cursor is positioned.
Edit	Switch to the edit mode.
EOF	Indicates whether the cursor is positioned after the last record in the recordset.
Field	Accesses the value of a field.
FieldByIndex	Gets or modifies the value of a field, referenced by its index.
FieldCount	Number of fields in the table.
FieldName	Name of a field in the table.
LookupUniqueID	Moves the cursor to the record identified by its UniqueID primary key.
MoveFirst	Moves the cursor to the first record.
MoveLast	Moves the cursor to the last record.
MoveNext	Moves the cursor to the next record.
MovePrevious	Moves the cursor to the previous record.
OpenTable	Opens a Palm database contained in a.pdb file.
RecordCount	Number of records in the recordset.
SortInfoBlock	Retrieves or modify the content of the sort info block.
Update	Updates a database record.

System	Minimal version	Remarks

Palm OS	Palm OS 3.0	N/A