<html> <head> <title></title> <script> //create array var beatles = new Array("1","2","3","4"); beatles = Array("1","2","3","4"); beatles = ["1","2","3","4"]; alert(beatles); // create object var person = Object(); person.name = "mguo"; person.gentle = "male"; person = {name:"mguo",gentle:"male"}; alert(person.name); // 未用var声明的变量看做全局变量 var total = 50; function square(num){ total = num * num; return total; } function square_(num){ var total = num * num; return total; } var number = square(20); alert(total); total = 50; var number_ = square_(20); alert(total); </script> </head> <body> </body> </html>