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function test(){
var m=n=1;
alert(m);
}
alert(n);
//ÒòΪtestº¯ÊýûÓÐÖ´ÐУ¬³Ì¶È¿ØÖÆÁ÷²»ÄܽøÈë½øÐнâÎö£¬ÀïÃæµÄ¶«Î÷¶ÔÍâÃæ²»¿É¼û£¬Òò´Ë±¨´í
function test(){
var m=n=1;
alert(m);
}
test();
alert(n);
//µ±testÖ´Ðкó£¬Í³Í³±ä³ÉÈ«¾Ö±äÁ¿
function test() {
return 1
+2
}
alert(test())
ÀàËÆµÄ»¹ÓУ¬ÓÉȺÀïµÄabcdÌṩ
function test() {
return 1
2
}
alert(test())
ÀàËÆµÄ»¹ÓУ¬ÓÉȺÀïµÄabcdÌṩ
function test() {
return
2
}
alert(test())
ÀàËÆµÄ»¹ÓУ¬ÓÉȺÀïµÄabcdÌṩ
function test() {
1
+2-
3
}
alert(test())
//¿¼²ìJavaScriptµÄEOS£¨·ÖºÅ£©ÎÊÌ⣬עÒâ²Ù×÷·ûÊÇ·ñ´æÔÚ
ÉÏÃæÕâÌâÒ²¿ÉÒÔÒý³öÕâôһÌ⣬ÓÉȺÀïµÄabcdÌṩ
function test() {
try {
return 1;
} finally {
return 2;
}
}
alert(test())
//Ò»¸öº¯ÊýÖ´ÐÐºó±Ø¶¨·µ»Ø£¨return£©Ò»¸ö½á¹û£¬Èç¹ûÔ­º¯ÊýÌåûÓÐreturnÓï¾ä±Ø·µ»Øundefined¡£
//Èç¹ûÀïÃæ´æÔÚÒì³£´¦Àí£¬finally¿éÖеÄreturn µÄÓÅÏȼ¶¸ßÓÚtry ¿éÖеÄreturn
alert(Number())
ÀàËÆµÄ»¹ÓУ¬ÓÉȺÀïµÄabcdÌṩ
alert(+" 3 ")
//²Î¼ûECMA3-5thµÄµÚ9.3½ÚÓë15.7.1½Ú¡£Èç¹ûNumber([value])µÄvalue²»´æÔÚ£¬Ôò·µ»Ø0
//Ò»¸ö×Ö·û´®±»Ö´ÐÐÁË¡°+¡±£¬¡°-¡±µÈ²Ù×÷£¬Ï൱ÓÚµ÷ÓÃÁËNumber(str)£¬ÕâʱÒ༴Ï൱ÓÚµ÷ÓÃÁËtoNumberº¯Êý
//ÕâÊÇÒ»¸öÄÚ½¨º¯Êý£¬Ö»´æÔÚÓÚJSÒýÇæÖУ¬¶ÔÓÚÕâ¸östrËü»áÖ´ÐÐtrim²Ù×÷£¬ÔÙÖ´ÐÐÊý×Öת»»£¬
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var a = +' Infinity ';
alert(typeof a) //number
//Èç¹û²»ÄÜת»»Ôò·µ»ØNaN
var add = function(el){
alert(el === el+1)
}
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add(Infinity)
add(Number.MAX_VALUE)
add(Number.POSITIVE_INFINITY)
add(Number.NEGATIVE_INFINITY)
alert([1,2,3,4,5][0..toString.length])
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javascriptÖÐevent.keycode

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 ......

JavaScript ´´½¨Àà/¶ÔÏóµÄ¼¸ÖÖ·½Ê½

ÔÚJSÖУ¬´´½¨¶ÔÏó£¨Create Object£©²¢²»ÍêÈ«ÊÇÎÒÃÇʱ³£ËµµÄ´´½¨Àà¶ÔÏó£¬JSÖеĶÔÏóÇ¿µ÷µÄÊÇÒ»ÖÖ¸´ºÏÀàÐÍ£¬JSÖд´½¨¶ÔÏó¼°¶Ô¶ÔÏóµÄ·ÃÎÊÊǼ«ÆäÁé»îµÄ¡£
JS¶ÔÏóÊÇÒ»ÖÖ¸´ºÏÀàÐÍ£¬ËüÔÊÐíÄãͨ¹ý±äÁ¿Ãû´æ´¢ºÍ·ÃÎÊ£¬»»Ò»ÖÖ˼·£¬¶ÔÏóÊÇÒ»¸öÎÞÐòµÄÊôÐÔ¼¯ºÏ£¬¼¯ºÏÖеÄÿһÏî¶¼ÓÉÃû³ÆºÍÖµ×é³É£¨ÌýÆðÀ´ÊDz»ÊǺÜÏñÎÒÃdz£Ìý˵µÄHASH±í¡¢× ......

Javascriptµ¼³öExcel

<!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; ......

JavaScript ¶¯Ì¬Êý×é ʵÀý


<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 ......

[·­Òë]High Performance JavaScript(005)

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 ......
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