An adrotator control is available in ASP.Net to ease the task of rotating the advertisement images in a web form. This control enables you to display a different image whenever you refresh the page. This adrotator control takes the information about the images that are to be displayed from an XML file which also have many other elements in it that are used by this control. First let us have a look at a sample advertisement file that is used by the adrotator control in ASP.Net.
Let us assume that the advertisement XML file is named as advt.xml. This file might look like,
<AlternateText>Site2 Main Page</AlternateText>
The XML file that is used for advertisements would have the root element as the element. This may have many AD child elements. The elements ImageUrl,NavigateUrl,AlternateText,Impressions and Keyword are found in the AD element. These elements identify the properties of the image that is displayed using the adrotator control.
The ImageUrl element specifies the path to the image that is displayed using the AdRotator control. Once a user clicks the image that is displayed the user is taken to the URL specified in the NavigateUrl element. The AlternateText element holds the text that is displayed when the image is not loaded. The text in this element is also used as a ToolTip in some of the browsers. The element Impressions has a number as a value. This number indicates how often the image is displayed with respect to other images. The more the value of the number in this element, the more is the frequency of the image that is displayed. The sum of all the impressions in the advertisement file should not exceed 2,047,999,999. Otherwise the AdRotator will throw an runtime exception. The Keyword element is used to give the category of the advertisement.
You can just drag and drop a AdRotator control in the webform and set its attributes if you are using Visual Studio .Net. The code that is generated for the AdRotator control might be something as given below:
<asp:AdRotator id="AdRotator1" Target="_self"
In the above code in the HTML file you could see that the AdvertisementFile attribute of the AdRotator control has the xml file “advt.xml”. The other attributes are ‘id’ and ‘Target’. During runtime the AdRotator control uses the controls like asp:HyperLink and asp:Image to display the image in the web form page. The size of the image that is displayed is limited by the size of the AdRotator control that is found in the page. So, if you want to display larger images you need to adjust the size of the AdRotator control during design time itself.
It is possible to modify the values of the ImageUrl,NavigateUrl and AlternateText programmatically. For this you can use the AdCreated event. Thus by using the AdCreated event the rendering of the AdRotator control can be controlled.
Thus the AdRotator control is an easy way to display and rotate advertisements and also to give preference to some advertisements by using the Impressions element of the advertisement xml file….