variable name as variable value?

Anon

Hi everyone,

I am trying to allow a user to designate the size of an array, and fill in the values of said array. The idea i came up with was to dynamically generate the data input page using a for() loop with a field for each array entry up to the desired size, named according to the value of $i. ($VAL_1_TYPE, $VAL_2_TYPE, etc.). The problem is that I can't find a way to get the values from these distinct variables into an array or any other usable form without explicitly accessing each possible variable name (up to $VAL_999_TYPE) because I can't dynamically generate the names. Is there a way to insert a variable value into the name of a variable (create a dynamically named variable), or convert the variable's name into a string? Other suggestions are also welcome, as I am sure there is a more efficient way of solving my problem.

Anon

yeppers, it is one of the more fun aspects of php. The trick is with the double $ ($$)

if:
$bob = 10
$george = "bob"

then:
$$george = 10

check it at:
http://www.php.net/manual/language.variables.variable.php

Anon

I hope this is correct. You want the user to designate the size of an array, fill the array with values, then read back from the array. You can do this by using an array in the html document, then letting php read from this array that you have created. Like below:
<?
echo "<form action=\"test.php\" method=post>";

Output the final array values

if (isset($what)) {
for ($i =0; $i < sizeof($what); $i++) {
echo "Array $i = " . $what[$i] . "<br>";
}
}

After user chooses size of array,

Allow user to input data into

else if (isset($size)) {
for ($i =0; $i < $size; $i++)
echo "Array [" . $i . "] : <input type=text name=what[$i] size=10><br>";
echo "<input type=submit value=\"Create Array\">";
}

Let user choose size of array

else {
echo "Sizeof Array <select name=size>";
for ($i =0; $i < 10; $i++)
echo "<option>$i</option>";
echo "</select><br>";
echo "<input type=submit value=\"Create\">";

}
?>

This does not use strings to name variables, it uses an array. Anyway, hope this helps. If I am way off track, please respond.

Mike J

Anon

Either of those solutions works for my problem. Thanks for your help!

Anon

2 more ideas:

Name the form fields as below:
<input type=text name="val_type[]">
<input type=text name="val_type[]">
<input type=text name="val_type[]">

... and PHP will automatically insert them into an array $val_type.

-OR-

Access a variable by its name like so:

<?php
$this_value = ${"val_$i_type"};
/
You can use curly brackets to access any variable by its string name.
/
?>

-Keegan

Anon

Thanks, that last one is exactly what I had in mind. Thanks for everyone's help!