16th chapter-Application and programming of data browsing parts (i) (1)

Data-browsing widgets are used primarily to display and edit data in database tables, so they are often referred to as data control parts or data-aware parts, which are on the Datacontrols page of the part selection board, Figure 16.1 shows all the data browsing widgets on the Datacontrols page, where the Tdbgrid part is used for full-screen display and editing of records in database tables, Tdbnavigator for navigating between data records, inserting records, deleting records, and posting modified records.

Figure 16.1 Parts on Datacontrols part Page

In table 16.1, we describe some of the features of each data browsing part on the Datacontrols part:

Table 16.1 Overview of the data browsing parts

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Part Name Attribute Description

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TDBGrid Displays the record information in the database table in grid form,

Columns can be created in the design phase using the field editor or in the

Use program settings in line procedure

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Tdbnavigator it provides a set of buttons for navigation in database tables, editing modifications,

Inserts, deletes records, and refreshes the display of data, Tdbnavigator

Contained control buttons can be selected at design time

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Tdbtext used to display field values for the current record in a database table

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Tdbedit used to display and edit the field values specified in the current record in the database table

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Tdbmemo is used to display a Memo field in a database table, and a Memo field can

To contain multiple lines of characters or even BLOBs (sophomore object) data

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Tdbimage used to display image fields and BLOB data in a database table

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Tdblistbox when a user edits a field that modifies the current record in the table, the part

is a list box that contains multiple selections from which the user can select

The value of an item as a field

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Tdbcombobox This part is a combo box when the user edits the current record in the Modify table

You can enter field values directly in a specified field in the

You can also click the part to select a field value from the Drop-down list box

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Tdbcheck a check box for displaying field information in a database, when a field in a table

Value matches the value of the Valuechecked property of the check box, the

check box is selected

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Tdbreadiogroup Use this part to provide users with a set of options, but users can only

Select a selectable option from

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Tdblookaplist when the user wants to edit the specified field of the current record in the database table,

Use this part to provide multiple options, which are available from the related

, and is provided to the user as a list box in the form

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Tdblookupcombo This part combines the functions of tdbedit parts and Tdbcombobox parts,

A user can enter field values directly into the part, or from the Drop-down

list box in the Drop-down list box to select an option, just the

Optional options are read from other related database tables.

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