28.4.3. Switches

A switch in PHP allows us to to take certain actions depending on the value of a certain variable, as in the following example, where we check the value of the $pa variable:

switch($pa) {
  case "showpage":
    showpage($pid, $page);
  break;
  case "list_pages_categories":
    list_pages_categories($cid);
  break;
  default:
    list_pages();
  break;
}

In case $pa has the value "showpage", we call the showpage() function, in case it has the value "list_pages_categories", we call the list_pages_categories() function. If $pa does not have any of these two values, or any value at all, we enter the default case and call list_pages(). See also PHP control structures.

Switch statements are often used in module development (especially in the module administration functions, see Section 21.4). So, if you declared in a module admin case file a switch like:

switch($func) {
     case "func-one":
     funct-one();
     break;    
}

you must call it through a link like:

http://www.yoursite.com/modules.php?mop=modload
&name=The_Web_Ring&file=index&func=func-one

If your function needs to have parameters (see Section 28.4.2), your switch will look like:

switch($func) {
    case "func-one":
    funct-one($xid, $xname);
    break;
}

and your link will have to be:

http://www.yoursite.com/modules.php?mop=modload
&name=The_Web_Ring&file=index&func=func-one&xid=$xid&xname=$xname

See also the ADDONS-MODULES file that came with your PHP-Nuke package.