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                      The respective array element is accessed by enclosing the index value in square brackets.




                2.12 ARRAY PROPERTIES AND METHODS

              JavaScript arrays have various built-in properties and methods. Some of those are:
              Length Property

              The length property of an array returns the number of array elements. For example:

                  const fruits = ["pineapple", "pear", "jackfruit", "strawberry"];
                  var lgth = fruits.length;  //This will return 4.

              Array Methods
              To  work  with  arrays  easily,  JavaScript  provides  many  built-in  methods  (special  functions)  that  help  you
              manipulate and manage array data.
              Here, the sample to perform array methods is:

              Fruits = ['Apple', 'Mango', 'Banana', 'Papaya'];
              Some methods of array are as follows:

                 Methods                Description                     Usage                      Output
               toString()    Converts an array into a string of the  Fruits.toString();  Apple,Mango, Banana,Papaya
                             array values separated by commas.
               pop()         Removes the last element in an array.  Fruits.pop();       Apple,Mango,Banana
               push()        Adds a new element at the end of the  Fruits.push('Orange');  Apple, Mango,Banan, Papaya, Orange
                             array.
               shift()       Removes the first member from the  Fruits.shift();         Mango, Banana, Papaya
                             array  and  "shifts" every  subsequent
                             element to a lower index.
               unshift()     Adds a new  element to an array  (at  Fruits.unshift("Grapes");  Grapes,  Apple,  Mango,  Banana,
                             the beginning),  and  "shifts" all other                   Papaya
                             elements to a higher index.
               join()        Join all array elements into a string.  Fruits.join('&');  tApple&Mango&Banana&Papaya
               concat()      Creates a new array  by merging  Fruits.concat(moreFruits); Applex, Mango,  Banana,  Papaya,
                             (concatenating) existing arrays.                           Orange, Kiwi
               slice()       Gives back a new array that has a copy  Fruits.slice(1, 3);  Mango, Banana
                             of the given array's part.
               reverse()     Changes the original array by reversing  Fruits.reverse();  Papaya, Banana, Mango, Apple
                             the order of the elements.
               sort()        Sorts a string array in ascending order  Fruits.sort();    Apple, Banana, Mango, Papaya
                             alphabetically.

              The detailed explanation of these methods is as follows:
              1.   The toString()  Method: The  toString() method  converts an  array  into a  string,  with  the  values
                 separated by commas. It does not modify the original array, but instead returns a string representation of
                 the array.

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