. 1 <! DOCTYPE HTML> 2 <HTML> . 3 <head> . 4 <Meta charset = "UTF-. 8"> . 5 <title> </ title> . 6 </ head> . 7 <body> . 8 <Script type = "text / JavaScript "> . 9 // use the function keyword-defined function: the function calls and has no defined function 10 Demo (); . 11 function Demo () { 12 is Alert ( 'function is called' ); 13 } 14 // in expression defined function (anonymous function):Defined functions and has the calling function, the former is defined, called after 15 var the demo1 = function() { 16 Alert ( 'function to jump out' ); . 17 }; 18 is the demo1 (); . 19 20 is 21 is // function parameter passing 22 is function demo2 (A, B) { 23 is the console.log ( 'function is called' ); 24 the console.log (A, B); 25 the console.log (arguments); 26 is for (I in arguments) { 27 the console.log (arguments [I]); 28 } 29 } 30 demo2 (100,200,300,400); 31 </script> 32 </body> 33 </html>