Function scrollleft () {var TLE = document. title; var first = TLE. charat (0); var last = TLE. substring (1, TLE. length); // obtain the current tititile text document. title = last + first;} // you can repeat setinterval ("scrollleft ()", 500); clearinterval (10000); // only execute setTimeout ("scrollleft () ", 500); cleartimeout (10000); // <body onbeforeunload =" window. event. returnvalue = 'hello' "> whether to close the current page // jump to the page navigate (http://www.baidu.com); // get Set the address location of the current browser. href = http://www.baidu.com; // page refresh window. location. reload (); // determines whether to press a key if (window. event. altkey) {alert ("Alt");} else {alert ("otherkey");} // disable onclick = alert ("data error"); window. event. returnvalue = false; // determines the screen resolution if (screen. width <1024 | screen. height <768) {alert ("the resolution is too low and cannot be displayed normally! ");} // Operate the clipboard clipboardData. getdata ("text"); clipboardData. setdata ("text", Val); clipboardData. cleardata ("text"); // forward and backward window. history. back (); window. history. forward (); window. history. go (-1); window. history. go (1); // used for nesting JavaScript scripts and advertising document. write ()