switch…case

[Control Structures]

描述

Like 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.

語法

switch (var) {
  case label1:
    // statements
    break;
  case label2:
    // statements
    break;
  default:
    // statements
    break;
}

參數

var: a variable whose value to compare with various cases. Allowed data types: intchar.
label1label2: constants. Allowed data types: intchar.

回傳

Nothing

範例程式碼

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
    break;
}

語法參考主頁面

86Duino 參考的文本是根據 Creative Commons Attribution-ShareAlike 3.0 License,部分文本是從 the Arduino reference 修改的。 參考中的代碼示例已發佈到公共領域。

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