The Javascript array includes() function will return true
if a value is found in an array or false
otherwise.
But is it possible to add multiple conditions to this function? Something like this:
myArray.includes("one", "two", "three")
Unfortunately the includes()
function does not have a multiple values search option, but we can simulate this with the help of others Javascript array functions.
Check for at least one value to be included in an array
Let's say we want to test if AT LEAST ONE value, from a given set, is present in a Javascript array.
We can do this by mixing the includes()
function and the some() function:
const myArray = ["one", "two", "three", "four", "five"]
const s1 = ["two", "seven"]
const s2 = ["zero", "ten"]
let result1 = s1.some(i => myArray.includes(i))
// result1 = true
let result2 = s2.some(i => myArray.includes(i))
// result2 = false
Check for all values to be included in an array
On the other side, if we want to check if ALL values are present in a Javascript array, we will use includes()
combined with the every() method:
const myArray = ["one", "two", "three", "four", "five"]
const s1 = ["two", "four"]
const s2 = ["one", "ten"]
let result1 = s1.every(i => myArray.includes(i))
// result1 = true
let result2 = s2.every(i => myArray.includes(i))
// result2 = false
Notes on the Javascript include() function
Some final notes on the include() function:
- it takes a second optional argument, as the index from there to start the search. For example
myArray.includes("Rob", 2)
will returntrue
if the"Rob"
value is found only after the index 2 of the array. The index is zero based. - the include function is case-sensitive. For example
["rob", "joe"].includes("Rob")
will returnfalse
.
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📖 50 Javascript, React and NextJs Projects
Learn by doing with this FREE ebook! Not sure what to build? Dive in with 50 projects with project briefs and wireframes! Choose from 8 project categories and get started right away.