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function test(){
var m=n=1;
alert(m);
}
alert(n);
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function test(){
var m=n=1;
alert(m);
}
test();
alert(n);
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function test() {
return 1
+2
}
alert(test())
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function test() {
return 1
2
}
alert(test())
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function test() {
return
2
}
alert(test())
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function test() {
1
+2-
3
}
alert(test())
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function test() {
try {
return 1;
} finally {
return 2;
}
}
alert(test())
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alert(Number())
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alert(+" 3 ")
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var a = +' Infinity ';
alert(typeof a) //number
//Èç¹û²»ÄÜת»»Ôò·µ»ØNaN
var add = function(el){
alert(el === el+1)
}
//ÇóelµÄÖµ£¬ÈÃel === el+1³ÉÁ¢£¡
//¿¼²ìjavascriptµÄÊýÖµ·¶Î§
add(Infinity)
add(Number.MAX_VALUE)
add(Number.POSITIVE_INFINITY)
add(Number.NEGATIVE_INFINITY)
alert([1,2,3,4,5][0..toString.length])
//0..Ï൱ÓÚ0.0.,ÕâÀï²»ÄÜÖ±½Óд0.to
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javascriptÖÐevent.keycode
keycode 8 = BackSpace BackSpace
keycode 9 = Tab Tab
keycode 12 = Clear
keycode 13 = Enter
keycode 16 = Shift_L
keycode 17 = Control_L
keycode 18 = Alt_L
keycode 19 = Pause
keycode 20 = Caps_Lock
keycode 27 = Escape Escape
keycode 32 = space space ......
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; ......
<html>
<body>
<script type="text/javascript">
//·½·¨Ò»
var num_arr= [];
for (var i = 0 ; i < 10 ; i ++)
{
num_arr[i] = i;
}
document.write(num_arr+'</br>');
//·½·¨¶þ
var obj_arr=new Array();
obj_arr[6]='ss';
document.write(obj_arr.len ......
µÚ¶þÕ Data Access Êý¾Ý·ÃÎÊ
One of the classic computer science problems is determining where data should be stored for optimal reading and writing. Where data is stored is related to how quickly it can be retrieved during code execution. This problem in JavaScri ......