Data Navigation and Actions Using C1DbNavigator

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This tutorial demonstrates the main features of the C1DbNavigator control. It is primarily used to navigate through data source rows, but it can also be used to perform common actions on data such as adding rows, confirming changes, updating the data source, refreshing from the data source (canceling changes), and others.

Create a new Windows Application project.
Place the following components on the form as shown in the figure:
- C1ExpressConnection (C1.Data.Express.C1ExpressConnection)
- C1ExpressTable1-2 (C1.Data.Express.C1ExpressTable)
- C1Label1-3 (C1.Win.C1Input.C1Label)
- DataGridView1-2 (System.Windows.Forms.DataGridView)
- C1DbNavigator1-3 (C1.Win.C1Input.C1DbNavigator)
- Button1 (System.Windows.Forms.Button)

From the Properties window, set the following properties for the C1Label and Button controls:

Control	Property	Value
C1Label1	TextDetached	True
C1Label1	Text	Customers:
C1Label2	TextDetached	True
C1Label2	Text	Orders:
C1Label3	TextDetached	True
C1Label3	Text	Update/Refresh:
Button1	Name	btnClose
Button1	Text	Close

Select the C1ExpressConnection1 component, go to the Properties window, open the ConnectionString property. Add the following to the ConnectionString property: Provider=Microsoft.Jet.OLEDB.4.0;Data Source="Documents\ComponentOne Samples\Common\C1NWind.mdb".

Set the properties of C1ExpressTable1-2 as follows:

Control	Property	Value
C1ExpressTable1	ConnectionComponent	C1ExpressConnection1
C1ExpressTable1	DbTableName	Customers
C1ExpressTable2	ConnectionComponent	C1ExpressConnection1
C1ExpressTable2	DbTableName	Orders

Also, you need to set the AutoIncrement property of the OrderID field in C1ExpressTable2, otherwise you will not be able to update data in the database: Select C1ExpressTable2, press the ellipsis button in the Properties window for the Fields property to open the Fields dialog box, select the OrderID field and set its AutoIncrement property to ClientAndServer. This is necessary because OrderID is an autoincrement field in the database, so it must be treated accordingly by C1DataExpress.
Create a master-detail relation between C1ExpressTable1 (master) and C1ExpressTable2 (detail):
Press the ellipsis button in the Relations property of the C1ExpressionConnection1 control to open the Relations dialog box.
In the dialog box, select Customers for Parent, Orders for Child, add a join with CustomerID for both Parent field and Child field, press OK to close the Relations dialog box.

To bind controls to the data source, set the following properties:

Control	Property	Value
DataGridView1	DataSource	C1ExpressConnection1
DataGridView1	DataMember	_Customers
C1DbNavigator1	DataSource	C1ExpressConnection1
C1DbNavigator1	DataMember	_Customers
DataGridView2	DataSource	C1ExpressConnection1
DataGridView2	DataMember	_Customers.Customers – Orders
C1DbNavigator2	DataSource	C1ExpressConnection1
C1DbNavigator2	DataMember	_Customers.Customers – Orders

Now C1DbNavigator1 allows us to navigate the master table Customers, and the detail table Orders. However, we want some more functionality for our navigator control. We want the user to be able to perform common data action pressing navigator buttons. Using the VisibleButtons property, show the following buttons for C1DbNavigator1-2: Add, Delete, Apply, Cancel. By default, a navigator control also shows the current row number and row count. To save space, hide this information be setting the PositionVisible property to False.

The third navigator control, C1DbNavigator3 is used to perform update and refresh for the whole data set (both tables Customers and Orders). To hide redundant navigator fields and buttons, set PositionVisible to False and select only two buttons, Update and Refresh in the VisibleButtons property. Update and Refresh buttons do not have built-in functionality, since their function may be different with different data sources. To make them work, you need to write code in event handlers. Create the following event handlers:

Visual Basic	Copy Code
Private Sub C1DbNavigator3_UpdateData(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles C1DbNavigator3.UpdateData Me.C1ExpressConnection1.Update() End Sub Private Sub C1DbNavigator3_RefreshData(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles C1DbNavigator3.RefreshData Me.C1ExpressConnection1.Fill() End Sub

Visual Basic

Copy Code

Private Sub C1DbNavigator3_UpdateData(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles C1DbNavigator3.UpdateData
    Me.C1ExpressConnection1.Update()
End Sub
 
Private Sub C1DbNavigator3_RefreshData(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles C1DbNavigator3.RefreshData
    Me.C1ExpressConnection1.Fill()
End Sub

C#	Copy Code
private void c1DbNavigator3_UpdateData(object sender, System.EventArgs e) { this.c1ExpressConnection1.Update(); } private void c1DbNavigator3_RefreshData(object sender, System.EventArgs e) { this.c1ExpressConnection1.Fill(); }

Copy Code

private void c1DbNavigator3_UpdateData(object sender, System.EventArgs e)
{
    this.c1ExpressConnection1.Update();
}
 
private void c1DbNavigator3_RefreshData(object sender, System.EventArgs e)
{
    this.c1ExpressConnection1.Fill();
}

Navigator buttons can be monochrome, color (ColorButtons property set to True) or changing their color when hovered over (ColorWhenHover property set to True). They can also be three-dimensional (standard) or flat depending on the ButtonStyle property. Set the following properties:

Control	Property	Value
C1DbNavigator1	ButtonStyle	Standard
C1DbNavigator1	C1DbNavigator1.ColorButtons	True
C1DbNavigator2	ButtonStyle	Standard
C1DbNavigator2	ColorButtons	True
C1DbNavigator3	ButtonStyle	Standard
C1DbNavigator3	ColorButtons	True

Using properties UIStrings and ButtonToolTips, it is also possible to change the text displayed in the navigator and to change button ToolTips. For instance, we could specify the first button ToolTip as “Select the first customer” instead of the default “First record”. These properties can also be used to localize your application.

Run the program and observe the following:

By pressing the navigator buttons, you can move through the rows. If you press the Next button and hold it for a certain time (determined by the MoveDelayFirst property), the current position will change automatically with frequency determined by the MoveDelayNext property.
You can jump to any row number by typing the number in the navigator position area in C1DbNavigator1. You can also use arrow keys and mouse wheel in that area to move to next or previous rows. HOME and END keys move to the first and last row. PAGE UP and PAGE DOWN keys or mouse wheel with CTRL key pressed to page through the rowset.
If you change the value in a grid cell and press Cancel, the modified value will revert to the original value.
You can add new rows with the Add button and delete rows with the Delete button.
You can send changes to the database with Update button and re-fetch data from the database (discarding the changes you may have made) with the Refresh button.