How to chain two class functions in php? [duplicate] - php

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PHP: Chaining Method Calls [duplicate]
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PHP method chaining or fluent interface?
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Closed 26 days ago.
I have a couple of functions in the same class that extends PDO.
One of them is sort of a shorthand function to make executing update sql queries a bit faster to write.
In practice i can write this:
$db->u('table_name SET column WHERE column',[$_POST['newValue'],$_POST['id']]);
and it would turn it into this:
/**
* "u" for UPDATE
*
* #param string $sql mysql query string
* #param string|array $V value(s) to be executed
* #param int $l set "LIMIT", defaults to "LIMIT 1"
* #param string|null $chk output a preview of the query with values (does not execute the query).
* #return int affected rows if success, error message if failed
*
*/
$u = $db->prepare("UPDATE table_name SET column = ? WHERE column = ? LIMIT 1");
$u->execute(["newValue", "99"]);
$rows = $u->rowCount(); // this is returned if everything was ok
Here's the part with this function:
class KD_DB extends PDO {
protected static $db = ''; // database connection object is made available through this variable with all the available PDO methods etc.
public function u($sql,$V=[],$l=1,$chk=null){
# HANDLE PARAMETERS
$chk_arr = [debug,check];
if(in_array($V,$chk_arr)){ $chk = $V; $V=[]; } // allow $chk as 2. parameter, and reset $V
if(in_array($l,$chk_arr)){ $chk = $l; $l=1; } // allow $chk as 3. parameter, and reset $l
//
# SPLIT SQL-STRING
$sql = str_replace('UPDATE ','',trim($sql)); // remove "UPDATE "
list($T,$sql)=explode(' ',$sql,2); // sepparate tablename ($T) from sql-string
list($F,$W) = explode(' WHERE ',$sql); // split sql-string into FIELD-list ($F) and WHERE-list ($W)
//
# BUILD NEW PARTS
$Fstr = str_replace(['SET ',','],['',' = ?, '],$F).' = ?'; // create new sql field-string
$Wstr = str_replace(',',' = ? AND ',$W).' = ?'; // create new WHERE-str
//
# CREATE NEW SQL STRING
$sql = "UPDATE $T SET $Fstr WHERE $Wstr ".($l==0?'':"LIMIT $l");
//
# DEBUG
$chk_str = '<code><big style="letter-spacing:.1em; line-height:1.5em;">'.__METHOD__.($chk?'(<i style="color:red;"><b>'.ltrim($chk,'kd_').'</b>: no data executed</i>)':'').'<br> prepare->("'.$sql.'");<br> ->execute(["'.(is_array($V)?implode('", "',$V):$V).'"]);<br> return ->rowCount();</big>'.KD::backtrace().'</code>';
if($chk===check){ return print($chk_str); }
if($chk===debug){ die($chk_str); }
//
# EXECUTE QUERY
try{
$q = $this->prepare($sql);
$q->execute(!is_array($V)?[$V]:$V);
return $q->rowCount();
}catch(PDOException $e){
return $e->getMessage();
}
//
}
}
The other function is a shorthand for if(){...}else{} that utilizes a couple of other functions to handle response messages, and an optional redirect at the end:
public function verify($dbh,$yep='',$nope='',$redirect=''){
# HANDLE PARAMETERS
// ... just code to allow using $nope and $redirect as 2. and 3. parmameters
//
if(is_int($dbh)&&$dbh>0){
if(defined('is_ajax')){ echo json_encode(['type'=>'success','msg'=>($yep?:'Vellykket'),'data'=>$dbh]); exit; }
KD::setSuccess($yep?:'Default success message if none is provided');
} else {
if(defined('is_ajax')){ echo json_encode(['type'=>'error','msg'=>($nope?:'OBS! Noe gikk galt'),'data'=>$dbh]); exit; }
KD::setError($nope?:'OBS! Default error message if none is provided');
}
if($redirect){
KD::redirect($redirect);
}
}
This is how I would use them in practice:
$upd = $db->u('table_name SET column WHERE column',[$_POST['newValue'],$_POST['id']]);
$db->verify($upd);
And that's OK.
But I would really like to do one of the following:
$upd = $db->u('table_name SET column WHERE column',[$_POST['newValue'],$_POST['id']])->verify();
$upd = $db->u('table_name SET column WHERE column',[$_POST['newValue'],$_POST['id']]);
$upd->verify()
I think this would be the most clean and shortest code to write:
$upd = $db->u('table_name SET column WHERE column',[$_POST['newValue'],$_POST['id']])->verify('Custom Success message','Custom error message',redirect);
So I suppose the question is "How can a chain the verify()-function to u()-function?"