Every case in switch is triggered in JS

Question

I have a little problem to solve a bug in my code regarding to switch case statements.

testvalue = 1

switch(testvalue){
                case 1:
                    console.log("Case 1 loaded");
                case 2:
                    console.log("Case 2 loaded");
                case 3: 
                    console.log("Case 3 loaded");
                case 4: 
                    console.log("Case 4 loaded");
                case 5:
                    console.log("Case 5 loaded");
                default:
                    console.log("Default case loaded");
            }

After I run this part of code, I get the following result in the console:

"Case 1 loaded" "Case 2 loaded" "Case 3 loaded" "Case 4 loaded" "Case 5 loaded" "Default case loaded"

I dont understand why JavaScript is going into every case I have even tho I have 1 as my testvalue and none of the other cases after the first one should be triggered. Is it because testvalue is getting treated as a boolean? When I apply "typeof" to testvalue I get "number" as a result so JS should know that this is not a boolean.

I hope this one is pretty easy to solve. Thats for any kind of help!

Does this answer your question? [Switch statement multiple cases in JavaScript](https://stackoverflow.com/questions/13207927/switch-statement-multiple-cases-in-javascript) — Tim Biegeleisen, Dec 26 '20 at 10:41
Does this answer your question? [Why was the switch statement designed to need a break?](https://stackoverflow.com/questions/252489/why-was-the-switch-statement-designed-to-need-a-break) — E_net4 - Krabbe mit Hüten, Dec 26 '20 at 11:30
Its a nice additional info I just checked out, thank you for the information! — Kubaghetto the fresh Testobun, Dec 26 '20 at 14:05

score 2 · Answer 1 · edited Dec 26 '20 at 11:28

2

JavaScript supports C style switch case fall through, which means unless there is a break specified, it will continue to execute all the subsequent cases.

In order to execute only one set of statements in a case block, you must end it with break;.

edited Dec 26 '20 at 11:28

E_net4 - Krabbe mit Hüten

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answered Dec 26 '20 at 10:42

Akash Kava

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Almost 100% guarantee this is a duplicate of some other question, and it also can be considered to be a problem caused by a typo. – Tim Biegeleisen Dec 26 '20 at 10:45
1

Akash Kava answered my question, thank you very much. Also Tim, its not a dublicate, I was already searching for it but could not find any same case of error I had. – Kubaghetto the fresh Testobun Dec 26 '20 at 10:52
I simply did not understand why I should need to put a break into every case at the end but with the help from Akash and tedd I got it now. Thx again! – Kubaghetto the fresh Testobun Dec 26 '20 at 10:54

Every case in switch is triggered in JS

1 Answers1