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1 ÓÃ||À´Ìî³äĬÈÏÖµ
var status = flight.status || "unknown";
2 ʹÓÃ&&·ÀÖ¹TypeError
flight.equipment.model //throw "TypeError"
flight.equipment && flight.equipment.model //undefined

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var a={},b={},c={};
document.writeln(a===b); //false
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var stooge = {
"first-name":"Jerome",
"last-name":"Howard"
};
var temp = function(){};
temp.prototype=stooge;
var another_stooge= new temp;
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if (typeof Object.beget !== 'function'){
Object.beget = function (o){
var F = function (){};
F.prototype = o;
return new F();
}
}
var another_stooge =Object.beget(stooge);
another_stooge["first-name"] = 'Harry';
document.writeln(another_stooge["first-name"]); //Harry
document.writeln(another_stooge["last-name"]); //Howard
document.writeln(stooge["first-name"]); //Jerome

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typeof¿ÉÒÔ·ÃÎÊÔ­ÐÍÁ´
document.writeln(typeof flight.toString); //function
hasOwnPropertyÔò²»ÐÐ
 document.writeln(flight.hasOwnProperty('toString')); //false
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var properties = [
"first-name",
"last-name"
];
for (var i = 0; i < properties.length; i+=1){
document.writeln(properties[i] + ": " + stooge[properties[i]]);
}
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anothet_stooge["first-name"] = "Jack";
document.writeln(anothet_stooge["first-name"]);//Jack
delete anothet_stooge["first-name"];
document.writeln(anothet_stooge["first-name"]);//Jerome
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var MYAPP= {}£»
MYAPP.stooge = {
//...
};