JS 手写 instanceof
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<title>Document</title>
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<script>
function myInstanceof(A, B) {
var BP = B.prototype;
while (A) {
if (A.__proto__ === BP) {
return true;
}
A = A.__proto__;
}
return false;
}
console.log(myInstanceof(Object, Function));
console.log(myInstanceof(Object, Object));
console.log(myInstanceof(Function, Object));
console.log(myInstanceof(Function, Function));
console.log(myInstanceof(Object, Array));
</script>
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