Note: If the values to concat are strings or numbers, their actual values are added to the returned array. If the values to concat are object references, the same object reference will be added, and not the object itself. This means that both the old and new array will now contain references to those object(s), with changes to the referenced object affecting both arrays.

This is a JavaScript1.6 feature, supported in Firefox1.5+ but NOT IE7 or below.

testfunction() is the function reference containing the desired test. Its syntax must conform to the below:

testfunction(elementValue, elementIndex, targetArray){
}

The three arguments are passed implicitly into the function, containing the current element value, index, plus the array being manipulated.

Example: Here's an example that quickly scans an array to make sure all of its elements' value is greater than 0.

var numbersarray=[2, 4, 5, -1, 34]

function isZeroAbove(element, index, array) {
 return (element > 0)
}

if (numbersarray.every(isZeroAbove)) //evaluates to false
 alert("All elements inside array is above 0 in value!")

The testfunction() accepts an optional parameter "thisobj", which you can pass in a different object to be used as the "this" reference within the function.

This is a JavaScript1.6 feature, supported in Firefox1.5+ but NOT IE7 or below.

testfunction() is the function reference containing the desired code to execute:

var numbersarray=[-3, 5, 34, 19]

function greaterThanFive(element, index, array) {
 return (element > 5)
}

var FiveplusArray=numbersarray.filter(greaterThanFive) //new array contains [34, 19]

This is a JavaScript1.6 feature, supported in Firefox1.5+ but NOT IE7 or below.

testfunction() is the function reference containing the desired code to execute:

var numbersarray=[-3, 5, 34, 19]

function outputarray(element, index, array) {
 document.write("Element "+index+" contains the value "+element+"<br />")
}

numbersarray.forEach(outputarray)

//Output:
//Element 0 contains the value -3
//Element 1 contains the value 5
//Element 2 contains the value 34
//Element 3 contains the value 19

This is a JavaScript1.6 feature, supported in Firefox1.5+ but NOT IE7 or below.

var fruits=["Apple", "Oranges", "Pork", "Chicken"]

alert(fruits.indexOf("Pork")) //alerts 2

var fruits=["Apple", "Oranges"]
var result1=fruits.join() //creates the String "Apple,Oranges"
var result2=fruits.join("*") //creates the String "Apple*Oranges"

This is a JavaScript1.6 feature, supported in Firefox1.5+ but NOT IE7 or below.

This is a JavaScript1.6 feature, supported in Firefox1.5+ but NOT IE7 or below.

testfunction() is the function reference containing the desired code to execute:

var numbersarray=[-3, 5, 34, 19]

function doubleIt(element, index, array) {
 return (element*2)
}

var doubledarray=numbersarray.map(doubleIt) returns [-6, 10, 68, 38]

See also unshift(value) below, which does the opposite by adding a new value to the beginning of an array (so formerly 1st element becomes 2nd, 2nd becomes 3rd etc).

This method returns the elements deleted from array.

This is a JavaScript1.6 feature, supported in Firefox1.5+ but NOT IE7 or below.

testfunction() is the function reference containing the desired code to execute:

var numbersarray=[-3, -34, 1, 32, -100]

function isZeroAbove(element, index, array) {
return (element > 0)
}

if (numbersarray.some(isZeroAbove)) //evaluates to true
alert("One or more elements inside array is above 0 in value!")

The testfunction() accepts an optional parameter "thisobj", which you can pass in a different object to be used as the "this" reference within the function.

If SortFunction is defined, the array elements are sorted based on the relationship between each pair of elements within the array, "a" and "b", and your function's return value. The three possible return numbers are: <0 (less than 0), 0, or >0 (greater than 0):

• Less than 0: Sort "a" to be a lower index than "b"
•  Zero: "a" and "b" should be considered equal, and no sorting performed.
•  Greater than 0: Sort "b" to be a lower index than "a".

Take a look at the following 3 distinct examples:

//Sort Alphabetically and ascending:
var myarray=["Bob","Bully","Amy"]
myarray.sort() //Array now becomes ["Amy", "Bob", "Bully"]

//Sort Alphabetically and descending:
var myarray=["Bob","Bully","Amy"]
myarray.sort()
myarray.reverse() //Array now becomes ["Bully", "Bob", "Amy"]

//Sort numerically and ascending:
var myarray2=[25, 8, 7, 41]
myarray2.sort(function(a,b){return a - b}) //Array now becomes [7, 8, 25, 41]

//Sort numerically and descending:
var myarray2=[25, 8, 7, 41]
myarray2.sort(function(a,b){return b - a}) //Array now becomes [41, 25, 8, 71]

//Randomize the order of the array:
var myarray3=[25, 8, "George", "John"]
myarray3.sort(function() {return 0.5 - Math.random()}) //Array elements now scrambled

To sort numerically, you need to compare the relationship between "a" to "b", with a return value of <0 indicating to sort ascending, and >0 to sort descending instead. In the case of the statement "return a - b", since whenever "a" is less than "b", a negative value is returned, it results in the array being sorted ascending (from small to large).

To sort randomly, you need to return a random number that can randomly be <0, 0, or >0, irrespective to the relationship between "a" and "b".

var fruits=["Apple", "Oranges"]
fruits.unshift("Grapes") //fruits becomes ["Grapes", "Apples", "Oranges"]