create dynamic variable

[topcoder1]

many times I have a php page that accepts many parameters and validate them

$userName=null;
$password=null;
$firstName=null;
$lastName=null;
if(isset($_POST['userName'])$userName=$_POST['userName'];
...

is there a way to dynamically create variable and then assign a value to it? for example is it possible to dyanmically create a variable $userName? 

I am thinking about something like this:

createVariable('userName');

$userName='hi';

thanks!

[akitchin]

in doing:

 

$userName = 'hi';

 

you are dynamically creating it.  do you mean is there a way to blanket-create all of your form fields as NULL before assigning them their POST values?  or do you mean is there a way to create a variable variable name?

[topcoder1]

I mean is there a way to do something like this:

$array=array("param1","param2"...);
foreach($el in $array){
   if(isset($_POST[$el])
      createVariableAndAssignValueTo($el, $_POST[$el]);
   else createVariableAndAssignValueto($el,null);
}
//now I have all my params!
echo($param1);
echo($param2);

does that make sense?
thanks

 

in doing:

 

$userName = 'hi';

 

you are dynamically creating it.  do you mean is there a way to blanket-create all of your form fields as NULL before assigning them their POST values?  or do you mean is there a way to create a variable variable name?

[Jessica]

<?
$array=array("param1","param2");
foreach($array AS $el){
   if(isset($_POST[$el])
      $el = $_POST[$el];
   }else{
      $el = null;
   }
}
?>

 

Why are you trying to create a function for something simple like assigning a variable?

[XaeroDegreaz]

Hi, you dynamically create and name your variables like this:

 

$value = "Blue";

 

${$value} = "Color";

 

echo ($Blue) //Prints out Color

 

Same with arrays:

 

$i[0] = "One";

$i[1] = "Two";

 

${"newVariable".$i[0]} = "Wow";

echo($newVariableOne) //Prints out Wow

 

Hope that helps.

[keeB]

Hi, you dynamically create and name your variables like this:

 

$value = "Blue";

 

${$value} = "Color";

 

echo ($Blue) //Prints out Color

 

Same with arrays:

 

$i[0] = "One";

$i[1] = "Two";

 

${"newVariable".$i[0]} = "Wow";

echo($newVariableOne) //Prints out Wow

 

Hope that helps.

 

That is so retardedly stupid and unreadable.

 

I can't ever think of a case where something like this is useful outside of obfuscation

 

Thanks for sharing it, though!

[XaeroDegreaz]

And....

 

You came in here to type all of that, but you didn't even offer a counter solution. Who's retarded here?

[topcoder1]

Hi, you dynamically create and name your variables like this:

 

$value = "Blue";

 

${$value} = "Color";

 

echo ($Blue) //Prints out Color

 

Same with arrays:

 

$i[0] = "One";

$i[1] = "Two";

 

${"newVariable".$i[0]} = "Wow";

echo($newVariableOne) //Prints out Wow

 

Hope that helps.

 

thanks a lot! that's what I want!

[topcoder1]

<?
$array=array("param1","param2");
foreach($array AS $el){
   if(isset($_POST[$el])
      $el = $_POST[$el];
   }else{
      $el = null;
   }
}
?>

 

Why are you trying to create a function for something simple like assigning a variable?

 

It's mainly for reducing the lines of code I have to write, for example if I have 100 params like this that I have to assign individiually, it's roughly 100 lines of code.  Now I can just do the above and have the same effect.  it's very useful I think.

[keeB]

And....

 

You came in here to type all of that, but you didn't even offer a counter solution. Who's retarded here?

 

I am not bashing you, more the language in this regard.

 

I didn't call you retarded, I hope you realize

[teng84]

i have actually use that in some case this ${x} helps me

i use this in choosing what class to be used

 

something like

if ($x=='red')

{

${red} == ill put here the class or css thing

}

 

i do this in the forms where if you missed it then it turns into red

 

[dbo]

Yeah that is a pretty obscure thing and certainly could be construed as unreadable. If you choose to do something like that I'd suggest putting it off in a function rather than making code look convoluted. I'd be interested in hearing more about the problem you're trying to solve as there may be an alternative method.

[topcoder1]

Yeah that is a pretty obscure thing and certainly could be construed as unreadable. If you choose to do something like that I'd suggest putting it off in a function rather than making code look convoluted. I'd be interested in hearing more about the problem you're trying to solve as there may be an alternative method.

 

in a typical php file that accepts parameters I do something like this:

$a=null;
$b=null;
$c=null;
//100 more lines like above
if(isset($_POST['a'])) $a=$_POST['a'];
if(isset($_POST['b'])) $a=$_POST['b'];
if(isset($_POST['c'])) $a=$_POST['c'];
//100 more lines like above
//now business logic
if($a !=null & b!=null){
}
else if($a!=null && c!=null){
}
else if($a==null && b==null & c!=null){
}

now I can do this and saves lots of repeative code. 

$array=array("a","b", "c",...); // 1 line instead of 200 lines...
foreach($array AS $el){
   if(isset($_POST[$el])
      $el = $_POST[$el];
   }else{
      $el = null;
   }
}
//then my business logic as usual
if($a !=null & b!=null){
}
else if($a!=null && c!=null){
}
else if($a==null && b==null & c!=null){
}

 

I am no php proficient. so Maybe there's other easy solution someone can point out.

thanks