Javascript-Arrays
An array is a single variable that is used to store various elements(hold more than one value at a time.). You want to store a list of elements and access them by a single variable.
Creating an Array:
Syntax:
var array_name = [item1, item2, ...];
Example:
<!DOCTYPE html>
<html>
<body>
<h2>JavaScript Arrays</h2>
<p id="demo"></p>
<script>
var cars = ["html", "css", "javascript"];
document.getElementById("demo").innerHTML = cars;
</script>
</body>
</html>
OUTPUT:
JavaScript Arrays
html,css,javascript
3 ways to construct array in JavaScript:
- By array literal
- By creating instance of Array directly (using new keyword)
- By using an Array constructor (using new keyword)
JavaScript array literal:
syntax :
var arrayname=[value1,value2.....valueN];
values are contained inside [ ] and separated by , (comma).
Example:
<html>
<body>
<script>
var emp=["Html","CSS","JAVASCRIPT"];
for (i=0;i<emp.length;i++){
document.write(emp[i] + "<br/>");
}
</script>
</body>
</html>
OUTPUT:
Html
CSS
JAVASCRIPT
JavaScript Array directly (new keyword):
syntax :
var arrayname=new Array();
new keyword is used to create instance of array.
Example:
<html>
<body>
<script>
var i;
var emp = new Array();
emp[0] = "HTML";
emp[1] = "CSS";
emp[2] = "JAVASCRIPT";
for (i=0;i<emp.length;i++){
document.write(emp[i] + "<br>");
}
</script>
</body>
</html>
OUTPUT:
HTML
CSS
JAVASCRIPT
JavaScript array constructor (new keyword):
Create an instance of an array by passing arguments in the constructor so that we don’t have to provide value explicitly.
Example:
<html>
<body>
<script>
var emp=new Array("hello","welcome","I2tutorials");
for (i=0;i<emp.length;i++){
document.write(emp[i] + "<br>");
}
</script>
</body>
</html>
OUTPUT:
hello
welcome
I2tutorials