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Event Driven Programming

Because the File Name argument causes ADO to load the associated provider, you cannot pass both
the Provider and File Name arguments.
The ConnectionString property is read/write when the connection is closed and read-only when
it is open.
Duplicates of an argument in the ConnectionString property are ignored. The last instance of any
argument is used.

12.3 Displaying Data from Database in Grid
We will start Visual Basic and insert an ADO control, a DataGrid and three command buttons.
Name the three command buttons as cmdAuthor, cmdTitle and cmdAll. Change their captions
to Display Author ,Display Book Title and Display All respectively. The design interface is
shown in Figure 12.1.

Figure 12.1: Displaying Data from Database in Grid.

Now you need to connect the database to the ADO data control. However, you need to make
one change. At the ADODC property pages dialog box, click on the Recordsource tab and select
1-adCmdText under command type and under Command Text(SQL) key in SELECT * FROM
book.
Next, click on the command buttton cmdAuthor and key in the following statements:
Private Sub cmdAuthor_Click()
Adodc1.RecordSource = “SELECT Author FROM book”

Adodc1.Refresh
Adodc1.Caption = Adodc1.RecordSource
End Sub
and for the command button cmdTitle, key in
Private Sub cmdTitle_Click()
Adodc1.RecordSource = “SELECT Title FROM book”

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