JavaScript中的最佳循环允许返回值？

Question

There are a few loops in javascript including forEach, some, map, and reduce. However, from what I currently understand, none of these are appropriate if you want to iterate through an array and return the value of a particular index. It seems like I am pretty much left with the standard for loop only. Is that true?

So for instance, if I have an array of objects... and I would like to find the index of the item with a particular value... could I use anything other than the regular for loop?

Answer 1

There is also the for ... of ... :

for (variable of iterable) {
  statement
}

Answer 2

You can use a JavaScript library http://underscorejs.org . It have plenty of functions. for your purpose you can use _.indexOf . it will eturns the index at which value can be found in the array

example:

var data=[1, 2, 3];
var index= _.indexOf(data, 2);

out put will be 1

Answer 3

Array.prototype.findIndex() , as suggested by @Andreas in comments.

You can pass in a function to findIndex() method and define your equality criteria in that function.

It will return the index of first array element, that satisfies the equality criteria defined in your function.

Answer 4

像大家所说的Array.prototype.findIndex（）或Array.prototype.indexOf（） 。

Answer 5

You could use foreach() rather than regular for.It is the simplest and you can iterate and get the index. For more info: JavaScript Array forEach() Method