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Use TDBRichView to edit hypertext documents stored in database field. Unit DBRV; Syntax TDBRichViewEdit = class(TCustomRichViewEdit) DBRichViewEdit does not display or edit its content if it is not linked to RVStyle component via Style property. The most important property settings can be done in the component editor for TRichView. In Delphi (C++Builder) IDE, right click the DBRichViewEdit object on the form, choose "Settings" in the context menu. If you decide to choose "Allow adding styles dynamically" mode, please set AutoDeleteUnusedStyles to True. If the application doesn't require the data-aware capabilities of TDBRichViewEdit, use TRichViewEdit instead, to conserve system resources. If the application doesn't require the editing capabilities of TDBRichViewEdit, use TDBRichView instead, to conserve system resources. Hierarchy TObject TPersistent TComponent TControl TWinControl TCustomControl Field Type This component must be linked to BLOB field. If you use RVF (RichView Format), the database field must have binary BLOB type (i.e. must have ability to store arbitrary binary data, without conversion and filtering of characters). For example, in Paradox Tables it is "Binary", in Microsoft Access tables it is "OLE Object". You can also use text BLOB field type (memo). Memo fields cannot store binary data, so it is impossible to store documents in RVF format in them (unless you exclude rvfoSaveBinary from RVFOptions). However, you can use memo fields:
Starting from Delphi 2006, Unicode memo fields (Field.DataType=ftWideMemo) are supported specially. TDBRichView does not attempt loading RVF from these fields. It tries to load Unicode RTF (RTF code converted from String to WideString) or Unicode text from them. Supported Data Formats The supported field formats are:
For all field types except for Unicode memos:
For Unicode memos:
Saving data to the field: OnSaveCustomFormat event allows saving data in your own format. If this event is not processed, documents are saved in FieldFormat. Events OnNewDocument event occurs when creating a new document or before loading an existing one from the field. When the document is loaded from the field, OnLoadDocument occurs. OnLoadCustomFormat and OnSaveCustomFormat allow saving and loading documents in custom formats. Examples Example 1: Using viewer-style methods in DBRichViewEdit (such as LoadRTF) Example 2: Inserting controls what can modify themselves in DBRichViewEdit (for example, inserting TEdit; user can modify its text) |