switch statement

The switch construct is used to select one value from some range of values.

Syntax

javascriptswitch (variable) {
  case 'value1':
    /*
      a code located here will be executed
      if the variable has value1
    */
  break;
  case 'value2':
    /*
      a code located here will be executed
      if the variable has value2
    */
  break;
  case 'value3':
    /*
      a code located here will be executed
      if the variable has value3
    */
  break;
  default:
    /*
      a code located here will be executed
      if the variable has some other value
    */
  break;
};

The comparison is done for strict equality. The default block is optional.

Example

Let's display the user's language depending on the variable lang value:

javascriptlet lang = 'ru';

switch (lang) {
  case 'ru':
    alert('rus');
  break;
  case 'en':
    alert('eng');
  break;
  case 'de':
    alert('deu');
  break;
  default:
    alert('language not supported');
  break;
};

Example

Let's display the year season, in which the value from the variable falls:

javascriptlet num = 3;

switch (lang) {
  case 1:
    alert('spring');
  break;
  case 2:
    alert('summer');
  break;
  case 3:
    alert('autumn');
  break;
  case 4:
    alert('winter');
  break;
};

See also