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Yes, we can nest the UpdatePanel control.
The AccordionExtender control is similar to the CollapsiblePanelExtender control. It allows you to group multiple collapsible panels in a single control. At the same time, it also manages the collapsed and expanded state of each panel; therefore, expanding one panel at a time. In other words, the AccordionExtender control does not support expanding two or more panels simultaneously. Instead, the header templates of all the panels are always visible so that you can click on any of them to display the hidden contents. By default, the AccordionExtender control opens with one panel as expanded.
The Step property sets the steps for numeric increment and decrement. The default value is 1.
The UpdatePanel control specifies the portions of a Web page that can be updated together. As the UpdatePanel control refreshes only a selected part of the Web page instead of refreshing the entire page with a postback, you get more flexibility to create rich and client-centric Web applications. Refreshing a selected part of the Web page is referred as partial-page update. You can add one or more UpdatePanel control in the Web page, which automatically participates in partial-page update without custom client script. The UpdatePanel control uses the UpdatePanel class to support the partial-page rendering.
XMLHttpRequest get the current state of the request operation by using the readyState property. This property checks the state of the object to determine if any action should be taken. The readyState property uses numeric values to represent the state.
You can find out that an AJAX request has been completed by using the readyState property. If the value of this property equals to four, it means that the request has been completed and the data is available.
The following validation controls are available in ASP.NET AJAX 4.0: • FilteredTextBoxExtender - Enables you to apply filtering to a text box. • MaskedEditExtender and MaskedEditValidator - Restricts a user to enter only a certain pattern of characters in the TextBox by applying a mask to the input. • ValidatorCalloutExtender - Attaches to the ASP.NET validators so that the error messages are not displayed as a simple text but as a balloon-style ToolTip. • NoBot - Prevents the spam/bot from filling the input forms automatically and uses the Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA), which is a type of challenge-response test to ensure that the response is not generated by the computer. • PasswordStrengthExtender - Measures the strength of the password text entered within the text box by validating with the different strength specified parameters
No, it is not possible.
No, you have to copy this file to the Bin folder of your application.
Extensible HTML (XHTML) is a markup language that provides the mixture expressions of HTML and XML. XHTML is a flexible markup language that enables automated processing by standard XML tools, which was difficult in HTML.
The different states of the XMLHttpRequest object are as follows: • Uninitialized - Refers to the state when the object has not been initialized. • Open - Refers to the state when the object has been created; however, the send function has not been invoked. • Sent -Refers to the state when the send function is invoked; however, the status and headers are not available. • Receiving - Refers to the state when the process is receiving data. • Loaded - Refers to the state when the procedure is completed and the entire data is available.
You can divide the ASP.NET AJAX architecture into two components - AJAX client architecture and AJAX server architecture.
ASP.NET AJAX includes the following controls: • ScriptManager • ScriptManagerProxy • UpdatePanel • UpdateProgress • Timer
We can pass parameters to the server using either the GET or POST method. The following code snippets show the example of both the methods: • Get: XmlHttpObject.Open("GET", "file1.txt", true); • Post: XmlHttpObject.Open("POST", "file2.txt", true);
The following controls are introduced with the new version of AJAX Control Toolkit: • SeaDragonExtender control - Refers to the control that is used to deeply zoom the images. You can zoom in or out the image or the particular portion of the image by using the mouse. You can also create a menu over the Seadragon control. This control is helpful when you want to analyze the image closely. • AsyncFileUploadExtender control - Refers to the control that provides the facility to upload and save the files on the server asynchronously. You can check the outcome either at the server or client side.
AJAX is a built-in functionality of .NET Framework 4.0. Therefore, you can run an AJAX application by just installing Microsoft Visual Studio 2010. However, to use extenders in your applications, you are required to install AJAX Control Toolkit and copy the AjaxControlToolkit.dll file to the Bin directory of your application.
The DynamicPopulateExtender control populates the contents of a control dynamically. It enables you to send an asynchronous call to the server that dynamically populates the contents of a control. The DynamicPopulateExtender control replaces the contents of a control with the result of a Web service or page method call.
The MinimumPrefixLength property sets the minimum number of characters that must be entered before getting suggestions from the Web service.
ASP.NET AJAX, mostly called AJAX, is a set of extensions of ASP.NET. It is developed by Microsoft to implement AJAX functionalities in Web applications. ASP.NET AJAX provides a set of components that enable the developers to develop applications that can update only a specified portion of data without refreshing the entire page. The ASP.NET AJAX works with the AJAX Library that uses object-oriented programming (OOP) to develop rich Web applications that communicate with the server using asynchronous postback.
The difference between synchronous and asynchronous postback is as follows: • Asynchronous postback renders only the required part of the page; whereas, synchronous postback renders the entire page for any postback. • Asynchronous postback executes only one postback at a time, that is, if you have two buttons doing asynchronous postback, the actions will be performed one by one; whereas, synchronous postback executes all the actions at once. • Asynchronous postback only modifies the update panel that raises the postback; whereas, synchronous postback modifies the entire page.
Client-side libraries contain built-in code to make asynchronous calls over XMLHTTP. These libraries automatically handle browser compatibility issues. These libraries are based on a programming model similar to ASP.NET.
A Web page cannot contain more than one ScriptManager control. You can use the ScriptManagerProxy control to add scripts to other pages; however to perform such an operation, you need to work with a master page that contains the ScriptManager control. If you have only few pages that need to register to a script or a Web service, then you should remove these pages from the ScriptManager control and add them as individual pages by using the ScriptManagerProxy control. If you include the scripts on the master page by the ScriptManager control, then the items get downloaded on each page that extends the master page, even if they are not necessary.
AJAX uses the following syntax to create an object: var myobject = new AjaxObject("page path"); The page path is the URL of the Web page containing the object that you want to call. The URL must be of the same domain as the Web page.
The ConformOnFormSubmit property determines whether or not the confirm dialog box should wait when the form is submitted for display.
The UpdateProgress control is somewhat related to the UpdatePanel control. The UpdateProgress control enables you to design a user-friendly interface when a Web page consists of a number of UpdatePanel controls for partial-page rendering. The UpdateProgress control makes you aware of the status information about the partial-page updates in the UpdatePanel control.