Creating Database Applications in VB - Part II

[VelMurugan]

Creating database applications in VB

You have learned how to create a simple database application using data control. In this lesson, you will work on the same application but use some slightly more advance commands. The data control support some methods that are useful in manipulating the database, for example, to move the pointer to a certain location. The following are some of the commands that you can use to move the pointer around:

    data_navigator.RecordSet.MoveFirst                       ' Move to the first record

    data_navigator.RecordSet.MoveLast                       ' Move to the last record

    data_navigator.RecordSet.MoveNext                      ' Move to the next record

    data_navigator.RecordSet.Previous                        ' Move to the first record

You can also add, save and delete records using the following commands:

    data_navigator.RecordSet.AddNew                          ' Adds a new record

    data_navigator.RecordSet.Update                           ' Updates and saves the new record

    data_navigator.RecordSet.Delete                            ' Deletes a current record

*note: data_navigator is the name of data control

In the following example, you shall insert four commands and label them as First Record, Next Record, Previous Record and Last Record . They will be used to navigator around the database without using the data control. You still need to retain the same data control (from example in lesson 19) but set the property Visible to no so that users will not see the data control but use the button to browse through the database instead. Now, double-click  on the command button and key in the codes according to the labels.

Code Select Expand

Private Sub Command2_Click()
dtaBooks.Recordset.MoveFirst
End Sub

Code Select Expand

Private Sub Command1_Click()                     
dtaBooks.Recordset.MoveNext     
End Sub

Code Select Expand

Private Sub Command3_Click()
dtaBooks.Recordset.MovePrevious
End Sub

Code Select Expand

Private Sub Command4_Click()
dtaBooks.Recordset.MoveLast
End Sub