是否有可能有多个例外的Try / Catch Throw

Question

i have the following code and i'm wondering if i can use try & catch as below:

class fun_database implements idbInfo{
    private $srvr=idbInfo::srvr_name;
    private $usr=idbInfo::usrnm;
    private $pass=idbInfo::psswrd;
    private $db=idbInfo::db_name;

    public function connct(){
        $hookup = new mysqli($this->srvr, $this->usr, $this->pass, $this->db);

        if ($hookup->connect_errno)     
        {
            throw new Exception("Error Processing Request", 1);
        }
    }

    public function sql_require_all($table_name, $table_col){
        $hookup = new connct();

        $result = $hookup->query("SELECT $table_col FROM $table_name");
            if($hookup->error()){
               throw new Exception("Error Processing Request", 1);
            }
        return $result->num_rows;
    }
}

This is a simple connection to the mysql and performing some querying there. Here is and the actual call of the functions above:

$conn = new fun_database();
    try{
        $result = $conn->sql_require_all('wordtypes', 'types');
    }
    catch(Exception $err){
        echo "Problems at:". $err->getMessage();
    }
    return "<option>".$result."</option>";

What i'm asking is a bit theory. Most probably this code is NOT WORKING (i didn't test it yet). I just want to know is it possible with one 'try' to 'catch' two exceptions (as you can see the first 'throw' is in the second method of fun_database, and the second 'throw' is in the first method of the same object which is only called from the second method).

sorry for making it too complicated but still can't figure it out id this structure of try/catch is working.

Answer 1

you can only catch different types of exception...

class fun_database implements idbInfo{
private $srvr=idbInfo::srvr_name;
private $usr=idbInfo::usrnm;
private $pass=idbInfo::psswrd;
private $db=idbInfo::db_name;

public function connct(){
    $hookup = new mysqli($this->srvr, $this->usr, $this->pass, $this->db);

    if ($hookup->connect_errno)     
    {
        throw new DomainException("Error Processing Request", 1);
    }
}

public function sql_require_all($table_name, $table_col){
    $hookup = new connct();

    $result = $hookup->query("SELECT $table_col FROM $table_name");
        if($hookup->error()){
           throw new Exception("Error Processing Request", 1);
        }
    return $result->num_rows;
}
}

Then:

try{
    $conn = new fun_database();
    $result = $conn->sql_require_all('wordtypes', 'types');
}
catch(DomainException $err){
    echo "This Problem at:". $err->getMessage();
}
catch(Exception $err){
    echo "That Problem at:". $err->getMessage();
}
return "<option>".$result."</option>";

you would need your class instantiation inside that try block though I believe.