ASP.NET 4 Unleased - p 64 doc

Just as you can with the DetailsView control, you can use the FormView control to display, page, edit, insert, and delete database records.. Furthermore, adding validation controls to Fo

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GridLines=”None”

HeaderText=”Movies”

CssClass=”movies”

HeaderStyle-CssClass=”header”

FieldHeaderStyle-CssClass=”fieldHeader”

AlternatingRowStyle-CssClass=”alternating”

CommandRowStyle-CssClass=”command”

PagerStyle-CssClass=”pager”

Runat=”server” />

<asp:SqlDataSource

id=”srcMovies”

ConnectionString=”<%$ ConnectionStrings:Movies %>”

SelectCommand=”SELECT Title,Director,InTheaters FROM Movies”

InsertCommand=”INSERT Movies (Title,Director,InTheaters)

VALUES (@Title,@Director,

</div>

</form>

</body>

</html>

You can use the FormView control to do anything that you can do with the DetailsView

control Just as you can with the DetailsView control, you can use the FormView control to

display, page, edit, insert, and delete database records However, unlike the DetailsView

control, the FormView control is entirely template-driven

I use the FormView control much more than the DetailsView control The FormView control

provides you with more control over the layout of a form Furthermore, adding validation

controls to FormView is easier than adding validation controls to a DetailsView control

WEB STANDARDS NOTE

By default, the FormView control renders an HTML table It creates an HTML table

that contains a single cell In ASP.NET 4, you can disable this by setting the

RenderOuterTable property to False This enables you to style the output using

CSS styles

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FIGURE 12.13 Displaying a database record with the FormView control

LISTING 12.19 ShowFormView.aspx

<%@ Page Language=”C#” %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.1//EN”

“http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd”>

html

{

background-color:silver;

}

#content

{

margins:auto;

Displaying Data with the FormView Control

You can display a database record with the FormView control by using an ItemTemplate

For example, the page in Listing 12.19 displays a record from the Movies database table

(see Figure 12.13)

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background-color:white;

font:14px Georgia,Serif;

}

</style>

<title>Show FormView</title>

</head>

<body>

<asp:FormView

id=”frmMovies”

DataSourceID=”srcMovies”

Runat=”server”>

<b>Directed By:</b>

<%# Eval(“Director”) %>

<br />

<b>Box Office Totals:</b>

<%#Eval(“BoxOfficeTotals”, “{0:c}”) %>

</ItemTemplate>

</asp:FormView>

<asp:SqlDataSource

id=”srcMovies”

SelectCommand=”SELECT Id,Title,Director,BoxOfficeTotals FROM Movies

WHERE Id=1”

</div>

</form>

</body>

</html>

The FormView control’s DataSourceID property points to the SqlDataSource control The

SqlDataSource control retrieves the first record from the Movies database table

The ItemTemplate contains databinding expressions that display the values of the Title,

Director, and BoxOfficeTotals columns The Eval() method retrieves the values of these

columns The databinding expression for the BoxOfficeTotals column formats the value of

the column as a currency amount

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Paging Through Data with the FormView Control

You can allow users to navigate through a set of data items by allowing paging You can

allow the FormView control to automatically render the paging interface, or you can use a

PagerTemplate to customize the paging interface

The page in Listing 12.20 automatically renders an additional row that contains buttons

for navigating between data items

LISTING 12.20 ShowFormViewPaging.aspx

html

{

}

#content

{

margins:auto;

width:600px;

padding:10px;

}

a

{

color:blue;

}

</style>

<title>Show FormView Paging</title>

</head>

<body>

<asp:FormView

id=”frmMovies”

AllowPaging=”true”

Runat=”server”>

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<b>Directed By:</b>

<br />

</ItemTemplate>

</asp:FormView>

<asp:SqlDataSource

id=”srcMovies”

SelectCommand=”SELECT Id,Title,Director,BoxOfficeTotals FROM Movies”

</div>

</form>

</body>

</html>

The FormView in Listing 12.20 includes an AllowPaging property assigned the value True

Adding this property generates the paging interface automatically

NOTE

You can enable Ajax paging for a FormView control in exactly the same way you enable

Ajax paging for a GridView or DetailsView control If you wrap the FormView control

in an UpdatePanel, you can page through the records in FormView without performing

a noticeable postback to the server

WARNING

This section describes user interface paging, which is not an efficient method to use

when paging through large record sets because all the data must be loaded into

mem-ory In Chapter 18, you learn how to implement data source paging

You can customize the appearance of the automatically rendered paging interface with the

PagerSettings property, which exposes the PagerSettings class The PagerSettings class

supports the following properties:

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Mode—Enables you to select a display mode for the pager user interface Possible

values are NextPrevious, NextPreviousFirstLast, Numeric, and NumericFirstLast

display

values are Bottom, Top, and TopAndBottom

If you need to customize the appearance of the paging interface completely, you can

create a PagerTemplate The page in Listing 12.21 uses the PagerTemplate to create a

custom paging interface The PagerTemplate displays the current page number It also

contains buttons for navigating to the previous and next page (see Figure 12.14)

FIGURE 12.14 Using a with the control

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LISTING 12.21 ShowFormViewPagerTemplate.aspx

html

{

}

#content

{

margins:auto;

width:600px;

padding:10px;

}

.frmMovies

{

width:100%;

}

</style>

<title>Show FormView Pager Template</title>

</head>

<body>

<asp:FormView

id=”frmMovies”

CssClass=”frmMovies”

Runat=”server”>

<b>Directed By:</b>

<br />

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</ItemTemplate>

<hr />

Page: <%# frmMovies.PageIndex + 1 %>

</div>

<asp:LinkButton

id=”lnkPrevious”

Text=”Previous Page”

CommandName=”Page”

CommandArgument=”Prev”

|

<asp:LinkButton

id=”lnkNext”

Text=”Next Page”

CommandName=”Page”

CommandArgument=”Next”

</div>

</PagerTemplate>

</asp:FormView>

<asp:SqlDataSource

id=”srcMovies”

SelectCommand=”SELECT Id,Title,Director,BoxOfficeTotals FROM Movies”

</div>

</form>

</body>

</html>

Each button contained in the PagerTemplate has both a CommandName and

CommandArgument property The CommandName is set to the value Page CommandArgument

specifies a particular type of paging operation

You can use the following values for the CommandArgument property:

Last—Navigates to the last page

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Prev—Navigates to the previous page

Next—Navigates to the next page

Editing Data with the FormView Control

You can edit a database record with the FormView control For example, you can use the page

in Listing 12.22 to edit any of the records in the Movies database table (see Figure 12.15)

LISTING 12.22 ShowFormViewEditing.aspx

html

{

}

#content

FIGURE 12.15 Editing a record with the FormView control

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{

margins:auto;

width:600px;

padding:10px;

}

a

{

color:blue;

}

</style>

<title>Show FormView Editing</title>

</head>

<body>

<asp:FormView

id=”frmMovies”

DataKeyNames=”Id”

Runat=”server”>

<b>Directed By:</b>

<br />

<hr />

<asp:LinkButton

id=”lnkEdit”

Text=”Edit Movie”

CommandName=”Edit”

</ItemTemplate>

<asp:Label

id=”lblTitle”

Text=”Movie Title:”

AssociatedControlID=”txtTitle”

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