方法，只取自身有的属性； hasDontEnumBug = !({toString: null}).propertyIsEnumerable('toString'),//ie6一下，！之后的内容为false; dontEnums = [ 'toString','toLocaleString','valueOf','hasOwnProperty','isPrototypeOf','propertyIsEnumerable','constructor' ],dontEnumsLength = dontEnums.length;

return function (obj) {
if (typeof obj !== 'object' && typeof obj !== 'function' || obj === null) throw new TypeError('Object.keys called on non-object');

var result = [];

for (var prop in obj) {
if (hasOwnProperty.call(obj,prop)) result.push(prop);
}

if (hasDontEnumBug) {
for (var i=0; i < dontEnumsLength; i++) {
if (hasOwnProperty.call(obj,dontEnums[i])) result.push(dontEnums[i]);
}
}
return result;
}
})()
};