奇怪的JavaScript getElementsByName未定义错误

Question

Okay, I've seriously got to be missing something or I'm crazy. Here's the code I'm having an issue with, it is inside an onchange event:

console.log( (this.parentNode.parentNode) );
// fine prints the elements

console.log( (this.parentNode.parentNode).getElementsByName('otherposition[]') );
// gives me undefined error

(this.parentNode.parentNode).getElementsByName('otherposition[]')[0].style.opacity = '1';
// same error.

Answer 1

getElementsByName是document一种方法，元素没有这种方法。