1. Overview
The release of the new technology .NET 3.5 and Visual Studio 2008 makes milestone contribution to the .NET strategy of Microsoft. In the Web development, it includes a powerful HTML Web designer which provides split-view editing, and the perfect CSS. Meanwhile, it makes its support to JavaScript better, including Intelligent hints and debug.
Microsoft issued the first preview version of ASP.NET 3.5 Extensions only 20 days after it released .NET 3.5. The final version is released in the first half of the year 2008, which contains more features of ASP.NET:
1. ASP.NET MVC Framework
2. Improvement of ASP.NET AJAX
3. ASP.NET Dynamic Data support
4. ASP.NET Silverlight support
5. ADO.NET Data services
In this article, I will display some of the new features of ASP.NET 3.5 Extensions though several simple examples.
2. ASP.NET MVC framework
The concept of MVC has been raised for many years. It divides the application implementation into three parts: Model to maintain the data status, View to display the user interface, Controller to handle the user interaction, operate Model and select View to display the data. The first concern of ASP.NET MVC Framework is separation for testing more conveniently. Meanwhile, it uses aspx page, template page and user control as View and provides powerful URL Routing Engine. I will show these features by examples.
Step1: set up Model, use LINQ to SQL to establish a Product data model
Step2： set up View, display the detailed information of Pdoduct by using an aspx page which inherited from a Generic ViewPage：
{
protected void Page_Load(object sender, EventArgs e)
{
}
show the data in aspx page, use <%=%> directly to label output
<div>
<h2>ProductDetail:</h2>
ProductId
Name：<%= ViewData.Name %><br /><br />
Descn：<%= ViewData.Descn %>
</div>
Step3：set up Controller，inherit from Controller base class，and add Action，at the same time, use product view to realize the data function and input data object that needs to be displayed.
{
[ControllerAction]
public void Index()
{
MSPetShopDataContext db = new MSPetShopDataContext();
ProductInfo productinfo = db.ProductInfos.Single(p => p.ProductId == “BD-03″);
}
}
Step4：select Path for Configuration，make configurations Application_Start：
{
RouteTable.Routes.Add(
new Route
{
Url = “[controller]/[action].mvc”,
Defaults = new { action = “Index”},
RouteHandler = typeof(MvcRouteHandler)
}
);
}
basicly, the proceedings are the four steps for setting up a application based on ASP.NET MVC Framework.
3. ASP.NET AJAX improvement
In the ASP.NET 3.5 Extensions, the most important improvement to ASP.NET AJAX is a better support to browser history that we can control the Back and Forward button more conveniently. It provides two ways for us to choose, using server-side control or Client-script. In the following, I will illustrate how to use server-side control to control the browser history.
add ScriptManager Control， and set its EnableHistory attribute as true，permit the history management of browser and OnNavigate handled as OnNavigateHistory function for dealing with navigation event. At the same time, set the EnableStateHash attribute as false to make modifications easier to perform. In real situations, we can decide whether to perform the Hash encryption as required:
<asp:ScriptManager runat=”server” ID=”ScriptManager1″
OnNavigate=”OnNavigateHistory”
EnableHistory=”true”
EnableStateHash=”false” />
Create Browser history point at the time of clicking button with the way of AddHistoryPoint：
public void ButtonClick(object sender, EventArgs e)
{
LabelHistoryData.Text = ((Button)sender).Text;
ScriptManager.GetCurrent(this).AddHistoryPoint(key, LabelHistoryData.Text);
}
Navigation processing：
public void OnNavigateHistory(object sender, HistoryEventArgs e)
{
LabelHistoryData.Text = Server.HtmlEncode(e.State[key]);
}
For demonstration，three button should be added on the page：
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click" />
<asp:AsyncPostBackTrigger ControlID="Button2" EventName="Click" />
<asp:AsyncPostBackTrigger ControlID="Button3" EventName="Click" />
</Triggers>
<ContentTemplate>
<asp:Panel runat="server" CssClass="box" ID="Content" Height="40px">
Date and Time:
<%= DateTime.Now.ToLongTimeString() %>
<br />
Page's refresh state:
<asp:Label runat="server" ID="LabelHistoryData" />
</asp:Panel>
</ContentTemplate>
</asp:UpdatePanel>
<p />
<asp:Button runat="server" ID="Button1" Text="Key 1" OnClick="ButtonClick" />
<asp:Button runat="server" ID="Button2" Text="Key 2" OnClick="ButtonClick" />
<asp:Button runat="server" ID="Button3" Text="Key 3" OnClick="ButtonClick" />
In the preceding, I mainly use the server-side approach to realize the support to browser history in ASP.NET AJAX, you can also use client script to manage browser history.