如何获取此代码中目标元素的索引？

var array = [1, 2, 3, 4, 5];
var targetElement = 3;
var index = array.indexOf(targetElement);
console.log(index); // 输出：2

var array = [{id: 1, name: 'John'}, {id: 2, name: 'Jane'}, {id: 3, name: 'Bob'}];
var targetElement = {id: 2, name: 'Jane'};
var index = array.findIndex(function(element) {
  return element.id === targetElement.id && element.name === targetElement.name;
});
console.log(index); // 输出：1

var targetElement = $('.target');
var index = targetElement.index();
console.log(index); // 输出：目标元素在父元素中的索引