Chuyển bộ gõ


Từ điển Máy Tính - Foldoc Dictionary
switch statement



switch statement

(programming)   (Or case statement, multi-way branch) A construct found in most high-level languages for selecting one of several possible blocks of code or branch destinations depending on the value of an expression. An example in C is

 switch (foo(x, y))  {  case 1:  printf("Hello
"); /* fall through */ case 2: printf("Goodbye
"); break; case 3: printf("Fish
"); break; default: fprintf(stderr, "Odd foo value
"); exit(1); }
The break statements cause execution to continue after the whole switch statemetnt. The lack of a break statement after the first case means that execution will fall through into the second case. Since this is a common programming error you should add a comment if it is intentional.

If none of the explicit cases matches the expression value then the (optional) default case is taken.

A similar construct in some functional languages returns the value of one of several expressions selected according to the value of the first expression. A distant relation to the modern switch statement is Fortran's computed goto.

Last updated: 1997-01-30




Giới thiệu VNDIC.net | Plugin từ diển cho Firefox | Từ điển cho Toolbar IE | Tra cứu nhanh cho IE | Vndic bookmarklet | Học từ vựng | Vndic trên web của bạn

© Copyright 2006-2024 VNDIC.NET & VDICT.CO all rights reserved.