variable variables

[mlitch 0]

My PHP-generated form file will generate any number of text fields called "recipient"+an integer, so "recipient1", "recipient2", etc The PHP file handling the form submission will not know how many fields there are, so I need to get something like the following logic:

 

$i=1;

$max=how many fields there are (it will know this from a mysqli_num_rows variable being passed)

while ($i <= $max) {

$recipient+$i = $_POST[recipient+$i]

}

 

In other words, as long as $i is less than or equal to the maximum number, generate a variable named "recipient" concatenated with $i and assign it the value of $_POST['recipient concatenated with $i'].

 

I can't wrap my little brain around this. Help?

[Techneut 2]

What is your problem actually? Because it seems you are not asking any question.

[mlitch 0]

I need to write PHP code to handle a form. The form may have zero or more fields that are named "recipient1", "recipient2", "recipient3", etc. If there are two fields, I need to capture those fields. If there are six, I need to capture all six. Maybe there are none.

 

I could write

 

if (isset($_POST['recipient1'])) {

$thisvariable1=$_POST['recipient1'];

}

 

if (isset($_POST['recipient2'])) {

$thisvariable2=$_POST['recipient2'];

}

 

if . . . and so on. Maybe I could do 10 of these, but what if the form has 11 fields (recipient1 through recipient11)? I can't just write a hundred "if" statements. Surely there's some way to write a code that allows me to replace the "1", "2", and so on with some variable.

 

The form itself will pass along how many fields there are. How can I use that number to automatically generate this kind of code that assigns the $_POST data to variables?

 

Does that make more sense? How can I do this? That's my question.

[mlitch 0]

To be more concrete, this code

 

echo $_POST['recipient1'];

echo '<br/>';

echo $_POST['recipient2'];

echo '<br/>';

echo $_POST['recipient3'];

echo '<br/>';

echo $_POST['recipient4'];

echo '<br/>';

$i=1;

while ($i<=$how_many) {

${"variable_$i"}=$_POST{"['recipient$i']"};

echo 'variable '.$i.' is ';

echo ${"variable_$i"};

echo '<br/>';

$i=$i+1;

}

yields this:

612113variable 1 is variable 2 is variable 3 is variable 4 is

Why can't I get the "while" loop to give me the same results as the statements before the "while" loop? (The variable $how_many equals 4 in this example.)

Edited May 20, 2015 by mlitch

[mlitch 0]

The problem is with how to use curly braces with the $_POST variable, because this code:

 

$i=1;

while ($i<=$how_many) {

${"variable_$i"}=1000+$i;

echo 'variable '.$i.' is ';

echo ${"variable_$i"};

echo '<br/>';

$i=$i+1;

}

yields (as I expect):

variable 1 is 1001variable 2 is 1002variable 3 is 1003variable 4 is 1004

[Ingolme 1,020]

Why don't you use an array? That's what they're for.

 

In the $_POST array you're supposed to wrap string indices in quotation marks. In PHP, the concatenation operator is ., not +.

$recipient = array();while ($i <= $max) {  $recipient[$i] = $_POST['recipient' . $i]}

[mlitch 0]

Because I'm not good with arrays . . . but now that I see how to use it, I will! Thank you for showing me how to deal with the POST variable!!!!!