php中异常处理方法小结

class NotFoundException extends Exception{}

class InputException extends Exception{}

class DBException extends Exception{}

function exception_uncaught_handler(Exception $e) {   
header('Content-type:text/html; charset=utf-8');   
if ($e instanceof NotFoundException)   
exit($e->getMessage());   
elseif ($e instanceof DBException)   
exit($e->getMessage());   
else   
exit($e->getMessage());   
}   
set_exception_handler('exception_uncaught_handler');

$this->resConn = mysql_connect ($CONFIGS['db_host'], $CONFIGS['db_user'], $CONFIGS['db_pwd']);   
if (false == is_resource($this->resConn))   
throw new DBException('数据库连接失败。'.mysql_error($this->resConn));

if (0 != strcmp($curAlbum->interest_id, $it))  

throw new NotFoundException('很抱歉，你所访问的相册不存在');

<?php
class customException extends Exception
{
public function errorMessage()
{
//error message
$errorMsg = 'Error on line '.$this->getLine().' in '.$this->getFile()
.': <b>'.$this->getMessage().'</b> is not a valid E-Mail address';
return $errorMsg;
}
}
 
$email = "someone@example.com";
 
try
 {
 //check if 
 if(filter_var($email, FILTER_VALIDATE_EMAIL) === FALSE)
  {
  //throw exception if email is not valid
  throw new customException($email);
  }
 //check for "example" in mail address
 if(strpos($email, "example") !== FALSE)
  {
  throw new Exception("$email is an example e-mail");
  }
 }
 
catch (customException $e)
 {
 echo $e->errorMessage();
 }
 
catch(Exception $e)
 {
 echo $e->getMessage();
 }
?>

function num($num){
 if ($num>1){//异常抛出条件
  $msg="数值不能大于1″;//异常提示信息
  throw new Exception($msg);//抛出异常
 }
 echo "数值小于1″;
}
//在 "try" 代码块中触发异常
try {
 num(3);
 echo "执行正常";
}
//捕获异常
catch (Exception $e){
 echo "错误信息：".$e->getMessage();//Exception()的系统方法获取异常信息
 echo "错误文件：".$e->getFile();//Exception()的系统方法获取异常文件名
 echo "行数：".$e->getLine();//Exception()的系统方法获取异常行数
}
//======================================================================
echo "<br>========================================================<br>";
//扩展基本异常类
function checkEmail($email){//定义一个可以抛出异常的判断EMAIL合法性的函数
 if (filter_var($email,FILTER_VALIDATE_EMAIL)==false){
  throw new checkEmailException($email);//抛出异常用EMAIL做参数
 }
 echo "邮件合法";
}
class checkEmailException extends Exception{//定义扩展异常类
 public function errormsg(){
  $msg="错误原因：".$this->getMessage()."不是一个合法的EMAIL地址！";
  $msg.="错误文件名：".$this->getFile();
  $msg.="错误行数：".$this->getLine();
  echo $msg;
 }
}
$email="email…..@chhua.com";
try {//触发异常
 checkEmail($email);
}
//捕获异常
catch (checkEmailException $e){
 $e->errormsg();
}
//==================================多个异常的捕获
echo "<br>===================================================<br>";
class ex1 extends Exception{//定义一个异常类
 public function msg(){
  $msg="错误原因：".$this->getMessage()."大于100<br>";
  $msg.="错误文件：".$this->getFile()."<Br>";
  $msg.="错误代码：".$this->getCode()."<br>";
  $msg.="行数：".$this->getLine()."<br>";
  echo $msg;
 }
}
class ex2 extends Exception{//定义一个异常类
        public function msg(){
  $msg="错误原因：".$this->getMessage()."等于100<br>";
  $msg.="错误文件：".$this->getFile()."<Br>";
  $msg.="行数：".$this->getLine()."<br>";
  echo $msg;
 }
}
$num2=100;
try {
 if ($num2>100){//当条件满足时触发
  throw new ex1($num2);
 }
 if ($num2==100){//当条件满足时触发
  throw new ex2($num2);
 }
}
catch (ex2 $e){//捕获触发的异常
 $e->msg();
}
catch (ex1 $e){//捕获触发的异常
 $e->msg();
}