National Instruments 374318A-01 用户手册

© National Instruments Corporation

Use the Measurement Studio switch and LED controls as Boolean controls 
in an ASP.NET Web application. You typically use a switch control to 
receive and control Boolean input in an ASP.NET Web application. You 
typically use an LED control to indicate a Boolean value in an ASP.NET 
Web application. The switch and LED controls are shown in Figure 2-18.

Figure 2-18.  Web Forms Switch Control in Vertical Toggle 3D Style and 

Web Forms LED Control in Square 3D Style

With the switch and LED controls and the classes that interface with the 
controls, you can perform the following operations:

•

Receive notification before or after the state of the control changes.

•

Specify the image format of the control as BMP, GIF, JPEG, or PNG.

For more information about using the switch and LED controls, refer to the Using 

the Measurement Studio Web Forms Switch and LED .NET Controls section in the 
NI Measurement Studio Help.

Use the AutoRefresh control to update a Web control or a group of Web 
controls on the client at a specified interval.

The AutoRefresh control renders JavaScript on the client to create a timer 
in the browser. When the timer elapses, the AutoRefresh updates the 
controls in the AutoRefresh group. For downlevel browsers, the controls 
update via postback. For uplevel browsers, the client-side script rendered 
by the AutoRefresh control uses a client callback to update the associated 
controls on the client without posting the page back to the server.