JavaScript Array every() Method
Example
Check if all the values in the ages array are 18 or over:
var ages = [32, 33, 16, 40];
function checkAdult(age) {
return age >= 18;
}
function myFunction() {
document.getElementById("demo").innerHTML = ages.every(checkAdult);
}
The result will be:
false
Try it Yourself »
More "Try it Yourself" examples below.
Definition and Usage
The every() method checks if all elements in an array pass a test (provided as a function).
The every() method executes the function once for each element present in the array:
- If it finds an array element where the function returns a false value, every() returns false (and does not check the remaining values)
- If no false occur, every() returns true
Note: every() does not execute the function for array elements without values.
Note: every() does not change the original array
Browser Support
The numbers in the table specify the first browser version that fully supports the method.
Method | |||||
---|---|---|---|---|---|
every() | Yes | 9.0 | 1.5 | Yes | Yes |
Syntax
array.every(function(currentValue,index,arr), thisValue)
Parameter Values
Parameter | Description | ||||||||
---|---|---|---|---|---|---|---|---|---|
function(currentValue, index,arr) | Required. A function to be run for each element in the array. Function arguments:
|
||||||||
thisValue | Optional. A value to be passed to the function to be used as
its "this" value. If this parameter is empty, the value "undefined" will be passed as its "this" value |
Technical Details
Return Value: | A Boolean. Returns true if all the elements in the array pass the test, otherwise it returns false |
---|---|
JavaScript Version: | 1.6 |
More Examples
Example
Check if all the values in the ages array are a specific number or over :
<p>Minimum age: <input type="number" id="ageToCheck" value="18"></p>
<button onclick="myFunction()">Try it</button>
<p>All ages above
minimum? <span id="demo"></span></p>
<script>
var ages = [32, 33,
12, 40];
function
checkAdult(age) {
return age >=
document.getElementById("ageToCheck").value;
}
function myFunction() {
document.getElementById("demo").innerHTML = ages.every(checkAdult);
}
</script>
Try it Yourself »
Example
Check if all the answer values in the array are the same:
<script>
var survey = [
{ name: "Steve", answer: "Yes"},
{ name: "Jessica", answer: "Yes"},
{ name: "Peter",
answer: "Yes"},
{ name: "Elaine", answer: "No"}
];
function isSameAnswer(el,index,arr) {
if
(index === 0){
return true;
}
else {
return (el.answer === arr[index - 1].answer);
}
}
function myFunction() {
document.getElementById("demo").innerHTML = survey.every(isSameAnswer);
}
</script>
Try it Yourself »
JavaScript Array Reference