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function - JavaScript switch strange behavior

I have following code snippets.

var caseObj = function () {

}

switch (typeof caseObj) {

    case "function":
        console.log("it is function");

    case "object":

        console.log("It is object now");
}

Its output is

it is function.
It is object now.

But typeof caseObj gives output function but it still evalutes case "object" case also.

How it is possible? Am I doing wrong anythig?

EDIT :

typeof caseObj is giving function,So it executing that case but it also executing object case.Why this strange behavior?

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1 Answer

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by (71.8m points)

The problem is not with the typeof, but you've missed the break statement in the case. That'll make the case like function OR object and execute the block of both the cases.

You missed the break; statement for the cases. This is the reason, of falling out in the next case.

The break statement terminates the current loop, switch, or label statement and transfers program control to the statement following the terminated statement.

var caseObj = function() {

}

switch (typeof caseObj) {

  case "function":
    document.write("it is function");
    break;

  case "object":

    document.write("It is object now");
    break;
}

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