asp.net - javascript skips steps and executes last command only -

can please me on js scraper coding tried create website uses asp-like coding...

we use website download our latest software training manuals, , there more 50 manuals have download clicking on each item every time. download managers won't work, these pdfs linked __dopostback() nodes. if use coding 1 entry only, works perfectly, moment start batching command, skips __dopostback until last entry has been reached, , executes 1 only. i've tried adding sleep command slow down process if issue, did, sleep script x-ms , skip task of saving file loop again.

note: i'm not experienced javascript, there may few issues coding below, , appreciated educating myself!

i'm using google chrome , javascript console run below script:

//sleep function found on stackoverflow slow down script cmdlet function sleep(milliseconds) {     var start = new date().gettime();     (var = 0; < 1e7; i++) {         if ((new date().gettime() - start) > milliseconds){             break;         }     } }  // node starts index 2, start there avoid errors var = 2;  while (i <= 15){     console.log (i);      // execute __dopostback(...) depending on int values     switch(i){         case 1: case 2: case 3: case 4: case 5: case 6: case 7: case 8: case 9:             var cmdlet = "gridviewlevel3$ctl0" + + "$lnkfolder3";             console.log (cmdlet);             __dopostback(cmdlet,'');             sleep(6000);             break;         case 10: case 11: case 12: case 13: case 14: case 15:             var cmdlet = "gridviewlevel3$ctl" + + "$lnkfolder3";             console.log (cmdlet);             __dopostback(cmdlet,'');             sleep(6000);             break;         default:             console.log("error!"); //handle exceptions here...             break;     };      = + 1; }