The effect of the target: two drop-down frames, the second followed the first change, using the client script JavaScript implementation in the ASP.NET environment.
Step 1: Establish a JavaScript script:
Create and register this JS script in Page_Load:
String scriptkey = "menuchange";
IF (! page.isstartupscriptregistered (scriptkey) &&! Page.ispostback)
{
String scriptblock =
