Multiple Variable Variables in PHP
I am fairly new to PHP and programming in general... I am attempting to use a foreach loop to set some options on a page I have created. It all works except for the last section, where I am attempting to assign variables dynamically, so I can use them outside the loop.
<?PHP
$array=array(foo, bar, baz);
foreach ($array as $option) {
// I have if statements to determine what $option_req
// and $option_status end up being, they work correctly.
$option_req="Hello";
开发者_StackOverflow社区$option_status="World";
$rh='Req_';
$sh='Status_';
$$rh.$$option=$option_req;
$$sh.$$option=$option_status;
}
echo "<br>R_Foo: ".$Req_foo;
echo "<br>S_Foo: ".$Status_foo;
echo "<br>R_Bar: ".$Req_bar;
echo "<br>S_Bar: ".$Status_bar;
echo "<br>R_Baz: ".$Req_baz;
echo "<br>S_Baz: ".$Status_baz;
?>
When the loop is finished, should this now give me six variables?
$Req_foo
$Status_foo
$Req_bar
$Status_bar
$Req_baz
$Status_baz
I have played with this a bit, searches on Google seem fruitless today.
To access some array item, just access some array item.
No loops required.
$req = array("foo" => 1,
"bar" => 2,
"baz" => 3,
);
echo $req['foo'];
plain and simple
Looks like PHP doesn't like the concatenation when you're trying to do an assignment. Try doing so beforehand, like so:
<?php
$array = array('foo', 'bar', 'baz');
foreach ($array as $option)
{
$option_req="Hello";
$option_status="World";
$rh = 'Req_';
$sh = 'Status_';
$r_opt = $rh.$option;
$s_opt = $sh.$option;
$$r_opt = $option_req;
$$s_opt = $option_status;
}
echo "<br>R_Foo: ".$Req_foo;
echo "<br>S_Foo: ".$Status_foo;
echo "<br>R_Bar: ".$Req_bar;
echo "<br>S_Bar: ".$Status_bar;
echo "<br>R_Baz: ".$Req_baz;
echo "<br>S_Baz: ".$Status_baz;
As other commenters suggested, this isn't a great practice. Try storing your data in an array, rather than just cluttering up your namespace with variables.
You could (though you should not!) do:
${$rh.$option} = ...
Variable variables don't work that way. You need to have one variable containing the string.
$opt_r = $rh.$option;
$$opt_r = $option_req;
$opt_s = $sh.$option;
$$opt_s = $option_status;
Also, make sure to quote your strings:
$array=array('foo', 'bar', 'baz');
I don't suggest using variable variables, but if you want to, this is how to do it.
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