The WebViewPortControl is a Web Forms control derived from the ASP.NET Image control. It is the server counterpart of the browser side JsViewPortControl, which provides a user interface for visualization of the viewport in relation to the "full range", and support interactive moving and resizing of the viewport.

Normally, controls are specified at design time by using ASP.NET tags, or by dragging and dropping the controls onto the Web Form in Visual Studio.

However, some applications may create controls dynamically on the fly during runtime (eg. during the Page Load event of the Web Form). In this case, the controls may not receive the "Page Init" event, as they are created after the event. The WebViewPortControl requires this event for certain functions. If you are creating WebViewPortControl on or after the Page Init event, please refer to WebChartViewer.OnPageInit on how to perform these functions in the Page Init event before the control is created.

In addition to sending chart images directly from memory to the browser, WebViewPortControl also supports storing the chart images as image files first, and sending the links to those files to the browser. Please refer to ASP.NET Output Methods with Viewers for additional information.

The followings list out the members that are specific to WebViewPortControl. Members inherited from the Image control are omitted. Please refer to Microsoft .NET documentation for members of the Image control.

Properties
Methods
Events