indexOf source npm

_.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. If array is sorted providing true for fromIndex performs a faster binary search.

Arguments

  1. array (Array)

    The array to search.

  2. value (*)

    The value to search for.

  3. [fromIndex=0] (number)

    The index to search from.

Returns (number)

Returns the index of the matched value, else -1.

Example

_.indexOf([1, 2, 1, 2], 2);
// => 1

// using `fromIndex`
_.indexOf([1, 2, 1, 2], 2, 2);
// => 3