Page 331 - Web Applications (803) Class 11
P. 331

Example:
                 <HTML>
                    <BODY>
                       for..in loop statement
                    </BR>
                       <script type = "text/javascript">
                             var days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday'];


                             for(const i in days){
                                document.write(i +" => " + days[i]);
                                document.write("</br>");
                             }
                             document.write("</br>");
                       </SCRIPT>
                    </BODY>
                     </HTML>
                 Output:
















                 The while Loop

                 The while statement or loop is used to repeat a set of instructions until a conditional expression returns True. Once the
                 expression returns False, the loop is terminated. Following is the syntax of the while loop in JavaScript:
                   initialisation_expression;
                   while (conditional_expression) {
                   //loop body
                   update_expression;
                   }
                 Where,

                 Ð Ðinitialisation_expression: In this expression, a variable is initialized. Unlike for loop, this section appears outside
                   the loop.

                 Ð Ðconditional_expression: Similar to for loop, this expression contains a logical condition which evaluates either True
                   or False.

                 Ð Ðupdate_expression: The loop control variable is updated here.









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