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en:reference:language:switchcase [2017/04/07 10:03] (current)
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 +====== switch / case statements ======
 +
 +Like [[zh:​reference:​language:​if|if]] statements, switch...case controls the flow of programs by allowing programmers to specify different code that should be executed in various conditions. In particular, a switch statement compares the value of a variable to the values specified in case statements. When a case statement is found whose value matches that of the variable, the code in that case statement is run.
 +
 +The break keyword exits the switch statement, and is typically used at the end of each case. Without a break statement, the switch statement will continue executing the following expressions ("​falling-through"​) until a break, or the end of the switch statement is reached.
 +
 +===== Example =====
 +<code cpp>
 +  switch (var) {
 +    case 1:
 +      //do something when var equals 1
 +      break;
 +    case 2:
 +      //do something when var equals 2
 +      break;
 +    default: ​
 +      // if nothing else matches, do the default
 +      // default is optional
 +  }
 +
 +</​code> ​
 +===== Syntax =====
 +<code cpp>
 +switch (var) {
 +  case label:
 +    // statements
 +    break;
 +  case label:
 +    // statements
 +    break;
 +  default: ​
 +    // statements
 +}
 +
 +</​code> ​
 +===== Parameters =====
 +
 +var: the variable whose value to compare to the various cases
 +
 +label: a value to compare the variable to
  
en/reference/language/switchcase.txt · Last modified: 2017/04/07 10:03 (external edit)