Similarly, the value of expression is 2, statements associated with case 2 will execute.Ĭ) If the value of expression does not equal to value-1, value-2, …., then none of the statement sequences will execute.ĭ) In this case, the default clause will execute, and then default statements will execute. For example, the value of expression is 1, then statements associated with case 1 will execute. JavaScript switch statement works as follows:Ī) When the switch statement execute, the value of the expression has successively compared with each case value like value-1, value2-, …ī) If a match found, the statement sequence following that case label executed. The flowchart of JavaScript switch statement for the selection process as shown in the below figure. In other words, the default clause handles the case when no match of any case in the switch statement found. Break statement terminates the loop.į) The default statement is optional and execute when none of the previous cases matched. The case labels must end with a colon (:).ĭ) The statement sequence is a list of statements and may contain zero or more statements.Į) After each case, a break statement is necessary inside the switch block to come out from the switch block. These constants have called case labels (or case clauses).Ĭ) A switch can have multiple case clauses depending on requirements and must be unique within a switch statement. Duplicate case values have not permitted.ī) value-1, value-2, value-3, … are constants or literals. The expression must be type compatible with each of the values specified in the case statements. Let us see the following example in action.The general syntax of using the switch statement in JavaScript has as follows: switch(expression)Ī) In the above switch syntax, an expression must be of integer, string, boolean, or character type. With the support of ES6 made available in most modern browsers, there will be cases where you do want to use let and const statements to declare block-scoped variables. Example 2: Block-scope variables within switch statements If the break statement is omitted, then the program continues execution at the next statement in the switch statement. ![]() By the convention of the switch statement, the default clause is the last, but it does not always be so.Īn optional break statement associated with each case clause label ensures that the program breaks out of the switch once the matched statement is executed and continues execution at the statement following the switch. ![]() If there is no default clause, then the program continues execution at the statement following the end of the switch. If multiple cases match, the first case is performed, even if the cases are unique if no match case is a clause found, the program looks for an optional default clause, and if it transfers the control to that case clause and executes the associated statements. It then looks for the first case whose expression evaluates the exact value as the result of the expression using the strict comparison = and transfers the control to that case clause, executing the associated statements. The switch statement first evaluates its expression. ![]() Const ps4Game = 'Spider-Man 2018 video game' switch (ps4Game)
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