When the page loads a large amount of data, the prompt "loading data" appears.

Code The implementation is as follows:
Protected void page_load (Object sender, eventargs E)
{
// Progress bar
Response. Write ("<Div id = 'mydiv 'style = 'font-size: 9pt'> ");
Response. Write ("_");
Response. Write ("</div> ");
Response. Write ("<SCRIPT> mydiv. innertext =''; </SCRIPT> ");
Response. Write ("<script language = JavaScript> ;");
Response. Write ("Var DOTS = 0; var dotmax = 10; function showwait ()");
Response. Write ("{var output; Output = 'loading data, please wait '; DOTS ++; If (DOTS> = dotmax) DOTS = 1 ;");
Response. Write ("For (VAR x = 0; x <dots; X ++) {output + = '·';} mydiv. innertext = output ;}");
Response. Write ("function startshowwait () {mydiv. style. Visibility = 'visible ';");
Response. Write ("window. setinterval ('showwait ()', 1000 );}");
Response. Write ("function hidewait () {mydiv. style. Display = 'none ';");
Response. Write ("window. clearinterval ();}");
Response. Write ("startshowwait (); </SCRIPT> ");
Response. Flush ();
Thread. Sleep (8000 );

}

Note:
1. There are more than one method. I only provide this method;
2. Pay attention to the reference of the namespace added to the thread;