Array:
Arrays in JavaScript. In JavaScript, array is a single
variable that is used to store different elements. Unlike most languages where
array is a reference to the multiple variable, in JavaScript array is a single
variable that stores multiple elements.
1. The Array object lets you store multiple values
in a single variable.
2. It stores a fixed-size sequential collection of elements of the same type.
3. An array is used to store a collection of data, but it is often more useful an array as a collection of variables of the same type.
Declaring an Array:
In JavaScript the array can
be created using
Array object. Syntax:
var a = new Array(10);
In above syntax array is created
of 10 elements.
Using new operator we can allocate
the memory dynamically for the arrays.
We can also define
array by following ways:
var fruits = new
Array( "apple", "orange", "mango" );
Initializing an Array:
Initializing is the process of assigning
a value when either a variable or array is declared.
While initializing an array:
1. Declare name of the array
2. Make use of the keyword new
3. Each value in array
as an array element & separated
by comma.
Example: var mylist= new Array(20,40,50,60)
` Access the Elements of an Array:
Array element can be access by referring to the index number. Syntax: array[index]
Array functions:
1. Length: It will return the length of array. Syntax: array.length();
2. Add:By using length function, we can add element in array.
Syntax: array[array.length];
3. Sort: The elements can be sorted using the built in function sort. Syntax: array.sort();
4. Join: For combining array elements into string we can use join() function. Syntax: array.join();
5. Shift(): Shift method removes the first element from an array and returns that element. Syntax: array.shift();
6. Push(): Push method appends the given element(s) in the last of the arrayand returns the length of the new array. Syntax: array.push(element)
7. Pop(): Pop method removes the last element from an array and returnsthat element. Syntax: array.pop();
8. Reverse(): Reverse method reverses the element of an array. The first array element becomes the last and the last becomes the first.
Syntax: array.reverse();
Conclusion: We understand the different array functionalities by executing JavaScript’s.
Practical No.3: Develop JavaScript to Array functionalities.
<html>
<body>
<script>
document.write("Array Functionalities :"+
"<br/>"); var a=[20,30,10,60,40];
document.write("1. The Length
of array is : "
+ a.length);
document.write("</br>");
document.write("2. Displaying Array
Elements:"); for (i=0; i<a.length; i++){
document.write(a[i] +
"<br/>");
}
document.write("3. The elements is Added in
array:" +"<br>"); a[a.length]=70;
a[a.length]=90;
document.write("Display Array Elements:"); document.write("</br>");
for
(i=0; i<a.length; i++){ document.write(a[i]
+ "<br/>");
}
a.sort();
document.write("4. Display Array Elements After
Sorting:"); document.write("</br>");
for
(i=0; i<a.length; i++){ document.write(a[i]
+ "<br/>");
}
var num=a.shift();
document.write("Removed
element is : " + num + "<br>"); document.write("5. Dispaly
Array element After
shift function is : "
+ "<br>"); for (i=0;i<a.length;i++){
document.write(a[i]
+ "<br>");
}
var length = a.push(100);
document.write("6. Dispaly
Array element After
push function is: " + a );
document.write("</br>");
var
element = a.pop();
document.write("7. Dispaly
Array element After
pop function is: " + a );
document.write("</br>");
var
arr = a.reverse();
document.write("8. Dispaly Array element
After Reverse function is: " + arr );
</script>
</body>
</html>
*********************************OUTPUT**********************
Array Functionalities :
1.
The Length of array is : 5
2.
Displaying Array
Elements:
20
30
10
60
40
3.
The elements is Added in array:
Display Array Elements:
20
30
10
60
40
70
90
4.
Display Array Elements After Sorting:
10
20
30
40
60
70
90
Removed element is : 10
5.
Dispaly Array element
After shift function
is :
20
30
40
60
70
90
6.
Dispaly Array element
After push function
is: 20,30,40,60,70,90,100
7.
Dispaly Array element
After pop function
is: 20,30,40,60,70,90
8.
Dispaly Array element
After Reverse function
is: 90,70,60,40,30,20
Practical
No.3: Develop JavaScript to Array functionalities on strings.
<html>
<body>
<script>
document.write("Array Functionalities :"+
"<br/>"); var
a=["Abhishek","Akshay","Aniket","Saurabh",];
document.write("<b>The Length of array is :</b> "
+ a.length);
document.write("</br>");
document.write("<b>Displaying Array
Elements:</b><br\>");
for
(i=0; i<a.length; i++){ document.write(a[i]
+ "<br/>");
}
document.write("<b>The elements is Added in array
is:</b> Mahesh and Vishal" + "<br>");
a[a.length]="Mahesh";
a[a.length]="Vishal";
document.write("<b>Display Array
Elements:</b>"); document.write("</br>");
for
(i=0; i<a.length; i++){ document.write(a[i]
+ "<br/>");
}
a.sort();
document.write("<b>Display
Array Elements After Sorting:</b>");
document.write("</br>");
for (i=0; i<a.length; i++){
document.write(a[i] + "<br/>");
}
var num=a.shift();
document.write("<b>Removed element
is :</b> " + num
+ "<br>");
document.write("<b>Dispaly
Array element After shift function is :</b> " +
"<br>");
for
(i=0;i<a.length;i++){ document.write(a[i] +
"<br>");
}
var
length = a.push("Anish"); document.write("<b>Dispaly
Array element After push function is:</b> " + a );
document.write("</br>");
var element = a.pop();
document.write("<b>Dispaly Array
element After pop
function is:</b> " + a );
document.write("</br>"); var arr =
a.reverse(); document.write("<b>Dispaly
Array element After Reverse function is:</b>" + arr );
</script>
</body>
</html>
*********************************OUTPUT**********************
Array Functionalities :
The Length of array is : 4
Displaying Array Elements:
Display Array Elements:
Abhishek Akshay Aniket Saurabh Mahesh Vishal
Display Array Elements After Sorting:
Comments
Post a Comment