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<html>
<head>
<mce:script type="text/javascript"><!--
function sendMessage(msg,obj){
if(arguments.length == 2)
obj.handleMsg(msg);
else
alert(msg);
}
//Ò»¸ö½ÓÊÜÈÎÒâÊýÁ¿²ÎÊý²¢½«Æäת»»ÎªÊý×éµÄº¯Êý
function makeArray(){
var arr = [];
for(var i = 0;i < arguments.length;i++){
arr.push(arguments[i]);
}
return arr;
}
function displayerror(msg){
//Èç¹ûûÓÐÌṩ²ÎÊý£¬ÀàÐ;ÍÊÇundefined
if(typeof msg == 'undefined'){
msg = "An error occurred.";
}
alert(msg);
}
//ÓÃÒ»¸ö±äÁ¿ÀàÐÍÁбíÑϸñ¼ì²éÒ»¸ö²ÎÊýÁбí
function strict(types,args){
if(types.length != args.length){
throw "Invalid number of arguments. Expectd "+
types.length+", received "+args.length+
" instead.";
}
//±éÀúËùÓвÎÊý£¬¼ì²éÀàÐÍ
for(var i = 0;i < args.length;i++){
if(args[i].constructor != types[i]){
throw "Invalid argument type. Expectd "+
types[i].name+", received "+
args[i].constructor.name+" instead.";
}
}
}
//´òÓ¡Óû§Áбí
function userList(prefix,num,users){
//±£Ö¤prefixÊÇ×Ö·û´®£¬numÊÇÊý×Ö£¬usersÊÇÊý×é
strict([String,Number,Array],arguments);
//±éÀú'num'¸öÓû§
for(var i = 0; i < num;i++){
//ÏÔʾÿ¸öÓû§µÄÐÅÏ¢
alert(prefix+": "+users[i]);
}
}
// --></mce:script>
</head>
<body>
<a onclick="sendMessage('how are you');">call1</a>
<a onclick="sendMessage('how are you',{handleMsg:function(msg){alert('This is a customer message:' + msg);}});">call2</a>
<a onclick="alert(makeArray(1,2,3,4,5));">call3</a>
<a onclick="displayerror();">call4</a>
<a onclick="displayerror('test');">call5</a>
<a onclick="userList('test',2,[1,2,3,4,5]);">call6</a>
</b
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ÓÃarguments¶ÔÏó¼ì²â´«µÝ¸øº¯ÊýµÄ²ÎÊý¸öÊý£ºarguments.length
function test(){
if(arguments.length == 1)
alert(arguments[0] + "£¬ÄãºÃ");
else if(arguments.length == 2)
alert(a ......
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transitional. ......
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µÚÒ»ÖÖ£¬ÀûÓÃmath.round
var original=28.453
1) //round "original" to two decimals
var result=Math.round(original*100)/100; //returns 28.45
2) // round "original" to 1 dec ......