The _.differenceWith() method is similar to _.difference() method that returns the array containing the values that are in the first array not in the second array but in _.differenceWith() all the elements of the first array are compared with the second array by applying comparison provided in third. It may be a little complex to understand by reading this but it will become simple when you see the example.
Syntax:
_.differenceWith(array, [values], [comparator])
Parameters: This method accept three parameters as mentioned above and described below:
- array: This parameter holds the array that values are checked or inspect.
- values: This parameter holds the value that need to be removed.
- comparator: This parameter holds the comparison invoked per element.
Return Value: This method returns an array according to the condition explained above.
Example 1:
const _ = require('lodash') Â Â let x = [1, 2, 3] Â Â let y = [2, 4, 5] Â Â let result = _.differenceWith(x, y, _.isEqual); Â Â console.log(result); |
Here, const _ = require('lodash') is used to import the lodash library into the file.
Output:
[1, 3]
So, here each element of the first array is compared with each element of the second array according to the third comparator, in our case its _.isEqual. So, if the value becomes equal it removes it.
Example 2:
const _ = require('lodash'); Â Â let x = [{a: 1}, {b: 2}, 6] Â Â let y = [{a: 1}, 7, 6] Â Â let result = _.differenceWith(x, y, _.isEqual); Â Â console.log(result); |
Output:
[{b: 2}]
Example 3:
const _ = require('lodash'); Â Â let x1 = [1, 2, 3] Â Â let y1 = [2, 4, 5] Â Â let result1 = _.differenceWith(x1, y1, _.isEqual); Â Â console.log(result1); Â Â let x2 = [{a: 1}, {b: 2}, 6] Â Â let y2 = [{a: 1}, 7, 6] Â Â let result2 = _.differenceWith(x2, y2, _.isEqual); Â Â console.log('\n\n', result2); |
Output:
Note: This will not work in normal JavaScript because it requires the library lodash to be installed.
