js中case switch

switch(expression) {
  case value1:
    // 当expression的值等于value1时执行的代码块
    break;
  case value2:
    // 当expression的值等于value2时执行的代码块
    break;
  // 可以有任意数量的case语句
  default:
    // 如果没有匹配的case，则执行default代码块
}

let day = new Date().getDay();

switch(day) {
  case 0:
    console.log('Sunday');
    break;
  case 1:
    console.log('Monday');
    break;
  case 2:
    console.log('Tuesday');
    break;
  case 3:
    console.log('Wednesday');
    break;
  case 4:
    console.log('Thursday');
    break;
  case 5:
    console.log('Friday');
    break;
  case 6:
    console.log('Saturday');
    break;
  default:
    console.log('Unknown day');
}

switch(value) {
  case 1:
    console.log('One');
    break; // 必须添加break
  case 2:
    console.log('Two');
    break;
  default:
    console.log('Default');
}

switch(value) {
  case 1:
    console.log('One');
    break;
  case 2:
    console.log('Two');
    break;
  default:
    console.log('Value not recognized');
}