I need multiple cases in switch statement in JavaScript, Something like:

switch (varName){   case "afshin", "saeed", "larry":       alert('Hey');       break;   default:       alert('Default case');       break;}

How can I do that? If there's no way to do something like that in JavaScript, I want to know an alternative solution that also follows theDRY concept.

• 1
  Sad that this syntax is not working :(

  Lars Flieger

  – Lars Flieger

  2021-08-26 11:46:10 +00:00

  CommentedAug 26, 2021 at 11:46
• 1
  the syntax is valid but it will only check on the last case, javascript should throw an error in such a case

  Isaac Weingarten

  – Isaac Weingarten

  2023-03-22 21:24:42 +00:00

  CommentedMar 22, 2023 at 21:24

26 Answers26

Here's different approach avoiding theswitch statement altogether:

var cases = {  afshin: function() { alert('hey'); },  _default: function() { alert('default'); }};cases.larry = cases.saeed = cases.afshin;cases[ varName ] ? cases[ varName ]() : cases._default();

In Javascript to assign multiple cases in a switch, we have to definedifferent case without break inbetween like given below:

   <script>      function checkHere(varName){        switch (varName)           {           case "saeed":           case "larry":           case "afshin":                alert('Hey');                break;          case "ss":               alert('ss');               break;         default:               alert('Default case');               break;       }      }     </script>

Please see example click onlink

I like this for clarity and aDRY syntax.

varName = "larry";switch (true){    case ["afshin", "saeed", "larry"].includes(varName) :       alert('Hey');       break;    default:       alert('Default case');}

If you're using ES6, you can do this:

if (['afshin', 'saeed', 'larry'].includes(varName)) {   alert('Hey');} else {   alert('Default case');}

Or for earlier versions of JavaScript, you can do this:

if (['afshin', 'saeed', 'larry'].indexOf(varName) !== -1) {   alert('Hey');} else {   alert('Default case');}

Note thatincludes won't work in some browser including older IE versions, but you could patch things up fairly easily. See the questiondetermine if string is in list in javascript for more information.

My situation was something akin to:

switch (text) {  case SOME_CONSTANT || ANOTHER_CONSTANT:    console.log('Case 1 entered');  break;  case THIRD_CONSTANT || FINAL_CONSTANT:    console.log('Case 2 entered');  break;  default:    console.log('Default entered');}

Thedefault casealways entered. If you're running into a similar multi-case switch statement issue, you're looking for this:

switch (text) {  case SOME_CONSTANT:  case ANOTHER_CONSTANT:    console.log('Case 1 entered');  break;  case THIRD_CONSTANT:  case FINAL_CONSTANT:    console.log('Case 2 entered');  break;  default:    console.log('Default entered');}

Adding and clarifyingStefano's answer, you can use expressions to dynamically set the values for the conditions in switch, e.g.:

var i = 3switch (i) {    case ((i>=0 && i<=5) ? i : -1):        console.log('0-5');        break;    case 6: console.log('6');}

So in your problem, you could do something like:

var varName = "afshin"switch (varName) {    case (["afshin", "saeed", "larry"].indexOf(varName)+1 && varName):      console.log("hey");      break;    default:      console.log('Default case');}

Although it is so muchDRY...

In Node.js it appears that you are allowed to do this:

data = "10";switch(data){    case "1": case "2": case "3": // Put multiple cases on the same                                  // line to save vertical space.        console.log("small");        break;    case "10": case "11": case "12":        console.log("large");        break;    default:        console.log("strange");        break;}

This makes for much more compact code in some cases.

Here is one more easy-to-use switch case statement. which can fulfill your requirement. We can use the find method in the switch statement to get the desire output.

    switch(varname){    case["afshin","saeed","larry"].find(name => name === varname):        alert("Hey")        break;    default:        alert('Default case');        break;}

I use it like this:

switch (true){     case /Pressure/.test(sensor):      {        console.log('Its pressure!');        break;     }     case /Temperature/.test(sensor):      {        console.log('Its temperature!');        break;     }}

Some interesting methods. For me the best way to solve is using.find.

You can give an indication of what the multiple cases are by using a suitable name inside your find function.

switch (varName){   case ["afshin", "saeed", "larry"].find(firstName => firstName === varName):       alert('Hey');       break;   default:       alert('Default case');       break;}

Other answers are more suitable for the given example but if you have multiple cases to me this is the best way.

It depends.Switch evaluates once and only once. Upon a match, all subsequent case statements until 'break' fire no matter what the case says.

var onlyMen = true;var onlyWomen = false;var onlyAdults = false;  (function(){   switch (true){     case onlyMen:       console.log ('onlymen');     case onlyWomen:       console.log ('onlyWomen');     case onlyAdults:       console.log ('onlyAdults');       break;     default:       console.log('default');   }})(); // returns onlymen onlywomen onlyadults

<script src="https://getfirebug.com/firebug-lite-debug.js"></script>

You can use the 'in' operator...
It relies on the object/hash invocation, so it's as fast as JavaScript can be.

// Assuming you have defined functions f(), g(a) and h(a,b)// somewhere in your code,// you can define them inside the object, but...// the code becomes hard to read. I prefer it this way.o = { f1:f, f2:g, f3:h };// If you use "STATIC" code can do:o['f3']( p1, p2 )// If your code is someway "DYNAMIC", to prevent false invocations// m brings the function/method to be invoked (f1, f2, f3)// and you can rely on arguments[] to solve any parameter problems.if ( m in o ) o[m]()

You can do this:

alert([  "afshin",   "saeed",   "larry",  "sasha",  "boby",  "jhon",  "anna",  // ...].includes(varName)? 'Hey' : 'Default case')

or just a single line of code:

alert(["afshin", "saeed", "larry",...].includes(varName)? 'Hey' : 'Default case')

a little improvement from ErikE's answer

I can see there are lots of good answers here, but what happens if we need to check more than 10 cases? Here is my own approach:

 function isAccessible(varName){     let accessDenied = ['Liam', 'Noah', 'William', 'James', 'Logan', 'Benjamin',                        'Mason', 'Elijah', 'Oliver', 'Jacob', 'Daniel', 'Lucas'];      switch (varName) {         case (accessDenied.includes(varName) ? varName : null):             return 'Access Denied!';         default:           return 'Access Allowed.';       }    }    console.log(isAccessible('Liam'));

The problem with the above approaches, is that you have to repeat the severalcases every time you call the function which has theswitch. A more robust solution is to have amap or adictionary.

Here is an example:

// The Map, divided by conceptsvar dictionary = {  timePeriod: {    'month': [1, 'monthly', 'mensal', 'mês'],    'twoMonths': [2, 'two months', '2 months', 'bimestral', 'bimestre'],    'trimester': [3, 'trimesterly', 'quarterly', 'trimestral'],    'semester': [4, 'semesterly', 'semestral', 'halfyearly'],    'year': [5, 'yearly', 'annual', 'ano']  },  distance: {    'km': [1, 'kms', 'kilometre', 'kilometers', 'kilometres'],    'mile': [2, 'mi', 'miles'],    'nordicMile': [3, 'Nordic mile', 'mil (10 km)', 'Scandinavian mile']  },  fuelAmount: {    'ltr': [1, 'l', 'litre', 'Litre', 'liter', 'Liter'],    'gal (imp)': [2, 'imp gallon', 'imperial gal', 'gal (UK)'],    'gal (US)': [3, 'US gallon', 'US gal'],    'kWh': [4, 'KWH']  }};// This function maps every input to a certain defined valuefunction mapUnit (concept, value) {  for (var key in dictionary[concept]) {    if (key === value ||      dictionary[concept][key].indexOf(value) !== -1) {      return key    }  }  throw Error('Uknown "'+value+'" for "'+concept+'"')}// You would use it simply like thismapUnit("fuelAmount", "ltr") // => ltrmapUnit("fuelAmount", "US gal") // => gal (US)mapUnit("fuelAmount", 3) // => gal (US)mapUnit("distance", "kilometre") // => km// Now you can use the switch statement safely without the need// to repeat the combinations every time you call the switchvar foo = 'monthly'switch (mapUnit ('timePeriod', foo)) {  case 'month':    console.log('month')    break  case 'twoMonths':    console.log('twoMonths')    break  case 'trimester':    console.log('trimester')    break  case 'semester':    console.log('semester')    break  case 'year':    console.log('year')    break  default:    throw Error('error')}

One of the possible solutions is:

const names = {afshin: 'afshin',saeed: 'saeed',larry: 'larry'};switch (varName) {   case names[varName]: {       alert('Hey');       break;   }   default: {       alert('Default case');       break;   }}

Cleaner way to handle that

if (["triangle", "circle", "rectangle"].indexOf(base.type) > -1){    //Do something}else if (["areaMap", "irregular", "oval"].indexOf(base.type) > -1){    //Do another thing}

You can do that for multiple values with the same result

If your case conditions are complex, many case value matches, or dynamic value match required, then it may be best to move that case matching logic to handler child functions.

In your case, if say you had thousands of usernames to match against for a security permissions check for example, this method is cleaner option, more extensible, exposing the high level multi-way branch logic without getting swamped in a long list of case statements.

    switch (varName)    {           case checkPatternAdministrator(varName):        alert('Hey');        break;      case checkPatternUserTypeA(varName):        alert('Hey2');        break;      case checkPatternUserTypeB(varName):        alert('Hey3');        break;      default:        alert('Default case');        break;    }

 function checkPatternAdministrator(varName) {    // Logic to check Names against list, account permissions etc.    // return the varName if a match is found, or blank string if not    var matchedAdministratorName = varName;    return matchedAdministratorName;  }

Another way of doing multiple cases in aswitch statement, when inside a function:

function name(varName){  switch (varName) {     case 'afshin':     case 'saeed':     case 'larry':       return 'Hey';     default:       return 'Default case';   }}console.log(name('afshin')); // Hey

Just change theswitch condition approach:

switch (true) {    case (function(){ return true; })():        alert('true');        break;    case (function(){ return false; })():        alert('false');        break;    default:        alert('default');}

You could write it like this:

switch (varName){   case "afshin":    case "saeed":    case "larry":        alert('Hey');       break;   default:        alert('Default case');       break;}

The switch statement is used to select one of many code blocks to execute based on a condition

1. the value in the switch expression is compared to the different values provided
2. if there is a match the code block related to it will be executed
3. if there is no match the default block is executed

syntax:

switch(expression) {  case x:    // code block    break;  case y:    // code block    break;  default:    // code block}

NOTE:It must be noted that if the break statement is omitted then the next block will be executed as well even if they does not match with switch expression. So don't forget to add the break statement at the end of each code block if you don't want to get the specified behaviour

A practical example:the following code returns the current day of the week in strings based on an integer (provided by 'new Date().getDay()')

switch (new Date().getDay()) {  case 0:    day = "Sunday";    break;  case 1:    day = "Monday";    break;  case 2:     day = "Tuesday";    break;  case 3:    day = "Wednesday";    break;  case 4:    day = "Thursday";    break;  case 5:    day = "Friday";    break;  case 6:    day = "Saturday";}

the code samples were taken fromW3Schools

<head>    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />    <title>Example1</title>    <link rel="stylesheet" href="css/style.css" >    <script src="js/jquery-1.11.3.min.js" type="text/javascript"></script>    <script>        function display_case(){            var num =   document.getElementById('number').value;                switch(num){                    case (num = "1"):                    document.getElementById("result").innerHTML = "You select day Sunday";                    break;                    case (num = "2"):                    document.getElementById("result").innerHTML = "You select day  Monday";                    break;                    case (num = "3"):                    document.getElementById("result").innerHTML = "You select day  Tuesday";                    break;                    case (num = "4"):                    document.getElementById("result").innerHTML = "You select day  Wednesday";                    break;                    case (num = "5"):                    document.getElementById("result").innerHTML = "You select day  Thusday";                    break;                    case (num = "6"):                    document.getElementById("result").innerHTML = "You select day  Friday";                    break;                    case (num = "7"):                    document.getElementById("result").innerHTML = "You select day  Saturday";                    break;                    default:                    document.getElementById("result").innerHTML = "You select day  Invalid Weekday";                    break                }        }    </script></head><body>    <center>        <div></div>        <center>            <h2> Switch Case Example </h2>            <p>Enter a Number Between 1 to 7</p>            <input type="text" />            <button>Check</button><br />            <div><b></b></div>        </center>    </center></body>

For me this is the simplest way:

switch (["afshin","saeed","larry"].includes(varName) ? 1 : 2) {   case 1:       alert('Hey');       break;   default:       alert('Default case');       break;}

• javascript
• switch-statement