Build Your Own ASP.NET 2.0 Web Site Using C# & VB, Second Edition

Figure 11.5. The styled address book

All the styling we need is already defined in the skin file; we’d only need to define

new properties if we wanted to alter the default values provided through the skin

file. Save your work and view the results in the browser. Do they look like the

display in Figure 11.5?

Congratulations! You’ve harnessed the power of CSS and skin files, and combined

it with the flexibility of GridView to easily create a good-looking address book!

As you can see, you can style the items in the GridView by altering their font

types, colors, and sizes. You can also style the column headers and apply an al-

ternating item style to alternate rows in the table. Now, when the GridView is

viewed in the browser, we see a little more room between cells, and the lines

surrounding the GridView are gone.

Selecting Grid Records

We’ve already made quite a few changes to the display of our GridView. The

next step will be to allow users to select one of the rows in the GridView so they

can view more information about the selected employee.

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Chapter 11: Managing Content Using Grid View and Details View

There are several types of columns that we can create in a GridView in addition

to the BoundField columns we’ve already seen. For instance, we could create a

ButtonField column, which displays a button in each row. The complete set of

column controls and their descriptions are listed here:

BoundField

As you’ve seen, the BoundField provides flexibility in presentation by allowing

you to specify which columns will appear within the GridView. When the

grid enters edit mode, this field renders itself as an editable text box, as we’ll

see later.

ButtonField

Use the ButtonField to display a clickable button for each row within the

GridView. When clicked, the button triggers a configurable event that you

can handle within your code to respond to the user’s action. The possible

event types that a button can trigger are: Cancel, Delete, Edit, Select, and

Update.

CheckBoxField

The CheckBoxField displays a checkbox in each row, allowing you to easily

present Boolean data in the display.

CommandField

The CommandField column automatically generates a ButtonField in your

grid. The actions performed by these buttons depend on the grid’s current

state. For example, if CommandField is set to generate Edit buttons, it will

display an Edit button when the grid is in non-editable mode, and will display

Update and Cancel buttons when the grid is being edited.

HyperLinkField

Use the HyperLinkField to display a clickable link within the GridView.

This link simply acts as a hyperlink to a URL; it raises no server-side events.

ImageField

This control displays an image inside your grid.

TemplateField

Use the TemplateField to display markup within the GridView.

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Selecting Grid Records

Figure 11.6. Adding a new GridView column

If you’re using Visual Web Developer, you can quickly and easily add a new

column to your table in Design View. Click the GridView’s smart tag, and click

the Add New Column... item, as shown in Figure 11.6.

In the dialog that appears, change the field type to ButtonField, the command

name to Select, and set the Text field to Select, so the dialog appears as it does

in Figure 11.7.

Figure 11.7. Adding a new field

After clicking OK, your brand new column shows up in Design View. If you switch

to Source View, you can see it there, too:

File: AddressBook.aspx (excerpt)

<asp:GridView ID="grid" runat="server"

AutoGenerateColumns="false">

<Columns>

<asp:BoundField DataField="Name" HeaderText="Name" />

<asp:BoundField DataField="City" HeaderText="City" />

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Chapter 11: Managing Content Using Grid View and Details View

<asp:BoundField DataField="MobilePhone"

HeaderText="Mobile Phone" />

<asp:ButtonField CommandName="Select" Text="Select" />

</Columns>

</asp:GridView>

If you execute the project now, and click the new button, the row will become

highlighted, as Figure 11.8 indicates. Notice that you didn’t write any code to

implement this feature? We’re relying on the functionality provided by the

ButtonField control when it’s CommandName property is set to Select, and the

style settings you set earlier, to produce this functionality.

Figure 11.8. Highlighting the selected field in the Address Book

We usually want extra work—in addition to the row highlight—to be performed

when a user selects a row in the address book. When the Select button is pressed,

the GridView fires the SelectedIndexChanged event, which we handle if we need

to do any further processing. We can generate the GridView’s SelectedIndex-

Changed event handler simply by double-clicking the GridView in the Visual

Web Developer designer.

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Selecting Grid Records