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Home php教程 php手冊 php異常處理技術(shù),頂級異常處理器

php異常處理技術(shù),頂級異常處理器

Jun 13, 2016 am 11:59 AM
exception php set function deal with processor definition abnormal technology yes of Top

定義頂級異常處理器用到的函數(shù)是
set_exception_handler("My_exception");
這里的My_expection是開發(fā)者自定義的異常處理函數(shù),既頂級異常處理器,只有當(dāng)程序中沒有函數(shù)來處理異常才有頂級異常處理器來處理異常,如果沒有定義頂級異常處理器,則由系統(tǒng)默認(rèn)的異常處理器來處理異常

舉例說明:

復(fù)制代碼 代碼如下:


set_exception_handler("My_expection");
function My_expection(){
echo "這里是頂級異常處理器";
}
try{
nohello("hello");
}catch(Exception $e){
throw $e;
}
  function nohello($nohello){
   if($nohello == "hello"){
   throw new Exception("不能輸入hello");
   }else{
echo "輸入成功";
}
}
?>


關(guān)于PHP異常處理 的一個問題

復(fù)制代碼 代碼如下:


try {
$a=10/0;
}catch (Exception $e){
echo "拋出異常";
}
?>


以上代碼,并不會輸出“拋出異?!?,而是輸出了錯誤信息:Warning: Division by zero in......

說明:try塊中并沒有拋出異常,而是按照系統(tǒng)默認(rèn)的錯誤處理機制進(jìn)行處理

所以能不能捕獲到異常,取決于有沒有真正的拋出異常
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