if to switch case javascript code example

Example 1: js switch case

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

Example 2: switch javascript

switch (a) {
    case 1:
        alert('case 1 executed');
        break;
    case 2:
        alert("case 2 executed");
        break;
   case 3:
        alert("case 3 executed");
        break;
    case 4:
        alert("case 4 executed");
        break;
    default:
        alert("default case executed");
}