Page 204 - Web Applications (803) Class 12
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There are several methods available for arrays and strings:

                   Method                   Description                                  Example
                    Name
                concat()       Joins two strings                      result = “Harry”.concat(“Potter”);
                                                                      document.write(result);
                                                                      Output: HarryPotter

                join()         Converts an array into a string        const animals = [“lion”, “tiger”, “cat”, “monkey”];

                                                                      var text1 = animals.join();
                                                                      document.write(text1+”<br>”);
                                                                      var text2=animals.join(“ and “);
                                                                      document.write(text2);

                                                                      Output:
                                                                      lion,tiger,cat,monkey
                                                                      lion and tiger and cat and monkey

                pop()          Removes the last element in an array   const languages = [“R”, “C”, “C++”, “Basic”];
                                                                      document.write(languages.pop());

                                                                      Output: Basic

                push()         Adds the new element at the end in an  const num = [10,20,30,40,50];
                               array                                  num.push(92);
                                                                      for(i=0;i<num.length;i++)

                                                                      document.write(num[i]+”,”);
                                                                      Output: 10,20,30,40,50,92,

                reverse()      The order of the elements in an array is  const fruits = [“pear”, “pinapple”, “guava”, “cherry”,
                               reversed via the reverse() method. The  “olive”];
                               original array is overwritten.         document.write(fruits.reverse());

                                                                      Output: olive,cherry,guava,pinapple,pear


                shift()        Returns  the  first  element  of  an  array  const fruits = [“pear”, “pinapple”, “guava”];
                               after removing it                      document.write(fruits.shift());
                                                                      Output: pear

                slice()        Selected array elements are returned as  const fruits = [“pear”, “pinapple”, “guava”, “cherry”,
                               a new array. The method begins from a  “olive”];

                               specified start and selects elements till  const list1 = fruits.slice(1, 3);
                               end-1 position.                        document.write(list1);

                               The original array remains unchanged.  Output: pinapple,guava







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