Lodash indexOf method
语法：
_.indexOf(array, value, [fromIndex=0])
Gets the index at which the first occurrence of value is found in array using SameValueZero for equality comparisons. If fromIndex is negative, it's used as the offset from the end of array.
参数
array (Array) − The array to inspect.
value (*) − The values to search for.
[fromIndex=0] (number) − The index to search from.
输出：
(number) − Returns the index of the matched value, else-1.
实例：
var _ = require('lodash');
var list = [1, 2, 3, 2, 5, 2];
var result = _.indexOf(list,2)
console.log(result);
var result = _.indexOf(list, 2, 3)
console.log(result);
Save the above program in
tester.js. Run the following command to execute this program.
命令：
输出：
