Switch to default case in switch-case

Question

Is it possible to go to the default case while I'm in case 1/2/etc.?

switch(num) {
    case 1:
        if(foo) {
            //do something
        } else {
            //go to default
        }

        ...
        ...
        ...

    default:
        //do something
}

Answer 1

Even if you change num value when you are in switch the value for comparision is the value of variable before start of switch so if you've entered one of case branches you cannot enter again into default .

However you can do something like

boolean doDefault = false;
switch(num) {
    case 1:
        if(foo) {
            ...
        }
        else {
            doDefault = true;
        }
        break;
}

if(doDefault) {
    //do something
}

Answer 2

You could write the logic that is supposed to happen in the default block in a function and call it when necessary:

void defAction(){
    printf("Hello, World!\n");
}

int main() {

    int num = 1, foo = 0;

    switch(num) {
        case 1:
            if(foo) {
                printf("Goodbye, World!\n");
            } else {
                defAction();
            }
            break;
        default:
            defAction();
    }

    return 0;
}

Remember, that if a case does not use break; , all cases below it (including default ) are also called. This way, if you only break out of the switch if(foo) , it will proceed to the default . This is only really useful, if you want to jump to default from no more than one case , in which case you put that case last, right before default .

use with caution / see comments below

switch(num) {
    case 2:
        // do sth
        break;
    case 3:
        // do sth
        break;
    case 4:
        // do sth
        break;
    case 1:
        if(foo) {
            printf("Goodbye, World!\n");
            break;
        }
        // ELSE don't break, use default
    default:
        defAction();
}

Answer 3

Not possible,doesn't make sense in real time application or in any use case,but if you want to go in default than you can do this by any of the following way-

1. Remove all break than you will meat default at end.
2. Call goDefault() method with value not matches with any case .

Answer 4

It's possible to make a method

switch(num) {
    case 1:
        if(foo) {
            //do something
        } else {
            foo();
        }
    default:
        foo();
    }

Answer 5

不，您不能，但是您可以调用相同的方法或忽略中断。

Answer 6

您可以将它们放在默认值之前，并且不要在大小写结束时刹车，然后无论情况如何，它将在中断之前执行所有语句

Answer 7

You achieve this in a way below.

Suppose you need to go to the default case after case 1,2,8 only then you can write below code.

 switch(Choice){
    case 1 : //do something
    case 2 : //do something
    case 8 : //do something
    default: //to do default operation   
    break;
    case 3 : 
    case 4 : 
  }