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ASP.NET PDF Viewer using C#, VB/NETUsed by the Output Cache module for moving return value of handler into the web server or client cache. Last chance to affect the output stream before it s sent back to IIS. Headers streamed out, and then content streamed out. qr code generator vb.net code project, devexpress barcode control winforms, winforms code 128, gs1 128 vb.net, ean 13 barcode generator vb.net, barcode pdf417 vb.net, c# remove text from pdf, c# replace text in pdf, vb.net data matrix generator, c# remove text from pdf,</head> <body> <form id="Form1" runat="server"> <h2>Displaying data</h2> <p> Compute primes from <asp:TextBox runat="server" id="LowerLimit" /> to <asp:TextBox runat="server" id="UpperLimit" />. </p> <asp:Button runat="server" id="GenerateData" text="Generate" OnClick="GenerateData_Click" /> <p> Results: <ul> <asp:Repeater id="Repeater" runat="server"> <ItemTemplate> <li style="color:blue"> n = <%# this.Eval("Item1") %>, time since previous: <%# this.Eval("Item2") %></li> </ItemTemplate> <AlternatingItemTemplate> <li style="color:green"> n = <%# this.Eval("Item1") %>, time since previous: <%# this.Eval("Item2") %></li> </AlternatingItemTemplate> </asp:Repeater> </ul> </p> </form> </body> </html> The application in Listing 14-6 consists of two input controls with the ASP.NET names LowerLimit and UpperLimit and an ASP.NET data-listing control called Repeater. The rest of the code is HTML markup and the F# embedded script to naively compute a sequence of prime numbers in the given range using the F# bigint type. The function isPrime implements the basic naive primality test. The computed value data is a list of tuples containing the prime numbers found in the given range. The type of each entry of this data list is (bigint * System.TimeSpan). This code demonstrates how to acquire input data from forms filled in by the client and how to display data grids back to the client. The input data is acquired simply by using page.LowerLimit.Text and page.UpperLimit.Text in the server-side event handlers. 100000 90000 Elapsed Time (Milliseconds) The data grid is generated by using the Repeater control to iteratively generate HTML; conceptually this is somewhat like a for loop that prints HTML at each step. Here is the relevant snippet: <asp:Repeater id="Repeater" runat="server"> <ItemTemplate> <li style="color:blue"> n = <%# this.Eval("Item1") %>, time since previous: <%# this.Eval("Item2") %></li> </ItemTemplate> <AlternatingItemTemplate> ... </AlternatingItemTemplate> </asp:Repeater> The repeater control contains two templates that define the HTML code that is generated during the iteration. It is common that subsequent lines use different formatting, and Repeater automatically switches between ItemTemplate and AlternatingItemTemplate. The body of the template uses somewhat cryptic ASP.NET constructs such as <%# this.Eval("Item1") %>. These are instances of one of the ASP.NET-embedded F# expression forms from Table 14-3. ASP.NET textually evaluates this element at each step of the repeated iteration. The repeater iterates over a data source. The data source can be specified either declaratively as we will see later or programmatically as in this example using the following lines: page.Repeater.DataSource <- data page.Repeater.DataBind() After the context of the request is established, the BeginRequest event is fired. Any Session variables that exist are not yet available, but Request and Response, having been established as part of the context, can be examined and exercised. You can check details of the request, such as the protocol the request came in on (Http or Https), details of the URL such as the file type being requested, or incoming cookies. BeginRequest is the first opportunity you have to extend the processing done in the pipeline. Afterward the security events, AuthenticateRequest and AuthorizeRequest, fire. These are the events that the ASP .NET programmers catch to implement the security models that ship with the Framework. For example, when the AuthenticateRequest fires and Formsbased authorization is set up in the web.config, a check is made to see if the authorization ticket cookie is part of the request. If it s not, the request is redirected to the URL specified in the configuration file for Forms-based authentication. In the authorization event, the users roles are checked against their allowed roles and the resource they re attempting to access (see 5 for details of these features). 80000 70000 Figure 14-2. Computing a data table using Listing 14-4
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