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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())
ÀàËÆµÄ»¹ÓУ¬ÓÉȺÀïµÄabcdÌṩ
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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//Èç¹ûtrimºóµÃµ½µÄΪInfinity£¬ÔòÖ±½Óת»»Ëü£¬È磺
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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var ob = function(){
var obj = this;
function fn1(){
alert( obj === window );//false
alert( this === window );//ture
}
this.fn2 = function() {
fn1();
}
}
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