floatval
As a note, get_defined_vars() does not return a set of variable references (as I hoped). For example:
<?php
// define a variable
$my_var = "foo";
// get our list of defined variables
$defined_vars = get_defined_vars();
// now try to change the value through the returned array
$defined_vars["my_var"] = "bar";
echo $my_var, "\n";
?>
will output "foo" (the original value). It'd be nice if get_defined_vars() had an optional argument to make them references, but I imagine its a rather specialized request. You can do it yourself (less conveniently) with something like:
<?php
$defined_vars = array();
$var_names = array_keys(get_defined_vars());
foreach ($var_names as $var_name)
{
$defined_vars[$var_name] =& $$var_name;
}
?>
get_defined_vars
(PHP 4 >= 4.0.4, PHP 5)
get_defined_vars — 返回由所有已定义变量所组成的数组
描述
array get_defined_vars
( void
)
此函数返回一个包含所有已定义变量列表的多维数组，这些变量包括环境变量、服务器变量和用户定义的变量。
<?php
$b = array(1,1,2,3,5,8);
$arr = get_defined_vars();
// 打印 $b
print_r($arr["b"]);
// 打印 PHP 解释程序的路径（如果 PHP 作为 CGI 使用的话）
// 例如：/usr/local/bin/php
echo $arr["_"];
// 打印命令行参数（如果有的话）
print_r($arr["argv"]);
// 打印所有服务器变量
print_r($arr["_SERVER"]);
// 打印变量数组的所有可用键值
print_r(array_keys(get_defined_vars()));
?>
add a note
User Contributed Notesget_defined_vars
donovan at example dot com
21-Oct-2008 09:15
21-Oct-2008 09:15
SyCo
21-Aug-2008 03:52
21-Aug-2008 03:52
Here's a very simple function for debugging. It's far from perfect but I find it very handy. It outputs the var value and the var name on a new line. The problem is it'll echo any vars and their name if they share the same value. No big deal when debugging and saves the hassle of writing the HTML and var name when echoing a variable. (ev=echo variable). Using get_defined_vars() inside a function renames the var name to the functions variable so isn't as useful for debugging. Of course, you'll need access to the $GLOBALS array
<?
function ev($variable){
foreach($GLOBALS as $key => $value){
if($variable===$value){
echo '<p>'.$key.' - '.$value.'</p>';
}
}
}
$a=0;
ev($a);
$b=0;
ev($b);
$c=0;
ev($c);
?>
Will output
a - 0
a - 0
b - 0
a - 0
b - 0
c - 0
kailashbadu at hotmail dot com
03-Mar-2007 03:09
03-Mar-2007 03:09
After a fruitless attempt find a built-in function whic did this, I wrote this functions to find out all the variables (well, those I wanted) in current scope and their values. I believe this is going to be handy in debugging.
<?php
/**
* @desc works out the variables in the current scope(from where function was called).
* Returns an array with variable name as key and vaiable value as value
* @param $varList: variables returned by get_defined_vars() in desired scope.
* $excludeList: variables to be excluded from the list.
* @return array
*/
function getDefinedVars($varList, $excludeList)
{
$temp1 = array_values(array_diff(array_keys($varList), $excludeList));
$temp2 = array();
while (list($key, $value) = each($temp1)) {
global $$value;
$temp2[$value] = $$value;
}
return $temp2;
}
/**
* @desc holds the variable that are to be excluded from the list.
* Add or drop new elements as per your preference.
* @var array
*/
$excludeList = array('GLOBALS', '_FILES', '_COOKIE', '_POST', '_GET', 'excludeList');
//some dummy variables; add your own or include a file.
$firstName = 'kailash';
$lastName = 'Badu';
$test = array('Pratistha', 'sanu', 'fuchhi');
//get all variables defined in current scope
$varList = get_defined_vars();
//Time to call the function
print "<pre>";
print_r(getDefinedVars($varList, $excludeList));
print "</pre>";
?>
william at avianhosting dot com
03-Nov-2006 12:41
03-Nov-2006 12:41
In response to sijmen at digitized dot nl and similar questions -- the problem is variable scope. $GLOBALS is used to access variables in the global scope from inside a function -- this is expected behavior, as get_defined_vars(); is supposed to get the -defined- variables -- and by default, variables in the global scope are -not- defined in the function scope. Therefore, if you want the variables from the global scope -- print_r($GLOBALS);.
zabmilenko at hotmail dot com
31-Aug-2006 07:32
31-Aug-2006 07:32
A little gotcha to watch out for:
If you turn off RegisterGlobals and related, then use get_defined_vars(), you may see something like the following:
<?php
Array
(
[GLOBALS] => Array
(
[GLOBALS] => Array
*RECURSION*
[_POST] => Array()
[_GET] => Array()
[_COOKIE] => Array()
[_FILES] => Array()
)
[_POST] => Array()
[_GET] => Array()
[_COOKIE] => Array()
[_FILES] => Array()
)
?>
Notice that $_SERVER isn't there. It seems that php only loads the superglobal $_SERVER if it is used somewhere. You could do this:
<?php
print '<pre>' . htmlspecialchars(print_r(get_defined_vars(), true)) . '</pre>';
print '<pre>' . htmlspecialchars(print_r($_SERVER, true)) . '</pre>';
?>
And then $_SERVER will appear in both lists. I guess it's not really a gotcha, because nothing bad will happen either way, but it's an interesting curiosity nonetheless.
sijmen at digitized dot nl
12-Jul-2004 08:11
12-Jul-2004 08:11
I was wondering what the difference was between get_defined_vars() and the array $GLOBALS. If you call get_defined_vars() not from a function, then there is no difference. But, if you call it from inside a function or class, then it will only return the available variables inside that function/class.
- Sijmen Ruwhof
lbowerh at adelphia dot net
04-Jun-2004 08:19
04-Jun-2004 08:19
Here is a function which generates a debug report for display or email
using get_defined_vars. Great for getting a detailed snapshot without
relying on user input.
<?php
function generateDebugReport($method,$defined_vars,$email="undefined"){
// Function to create a debug report to display or email.
// Usage: generateDebugReport(method,get_defined_vars(),email[optional]);
// Where method is "browser" or "email".
// Create an ignore list for keys returned by 'get_defined_vars'.
// For example, HTTP_POST_VARS, HTTP_GET_VARS and others are
// redundant (same as _POST, _GET)
// Also include vars you want ignored for security reasons - i.e. PHPSESSID.
$ignorelist=array("HTTP_POST_VARS","HTTP_GET_VARS",
"HTTP_COOKIE_VARS","HTTP_SERVER_VARS",
"HTTP_ENV_VARS","HTTP_SESSION_VARS",
"_ENV","PHPSESSID","SESS_DBUSER",
"SESS_DBPASS","HTTP_COOKIE");
$timestamp=date("m/d/y h:m:s");
$message="Debug report created $timestamp\n";
// Get the last SQL error for good measure, where $link is the resource identifier
// for mysql_connect. Comment out or modify for your database or abstraction setup.
global $link;
$sql_error=mysql_error($link);
if($sql_error){
$message.="\nMysql Messages:\n".mysql_error($link);
}
// End MySQL
// Could use a recursive function here. You get the idea ;-)
foreach($defined_vars as $key=>$val){
if(is_array($val) && !in_array($key,$ignorelist) && count($val) > 0){
$message.="\n$key array (key=value):\n";
foreach($val as $subkey=>$subval){
if(!in_array($subkey,$ignorelist) && !is_array($subval)){
$message.=$subkey." = ".$subval."\n";
}
elseif(!in_array($subkey,$ignorelist) && is_array($subval)){
foreach($subval as $subsubkey=>$subsubval){
if(!in_array($subsubkey,$ignorelist)){
$message.=$subsubkey." = ".$subsubval."\n";
}
}
}
}
}
elseif(!is_array($val) && !in_array($key,$ignorelist) && $val){
$message.="\nVariable ".$key." = ".$val."\n";
}
}
if($method=="browser"){
echo nl2br($message);
}
elseif($method=="email"){
if($email=="undefined"){
$email=$_SERVER["SERVER_ADMIN"];
}
$mresult=mail($email,"Debug Report for ".$_ENV["HOSTNAME"]."",$message);
if($mresult==1){
echo "Debug Report sent successfully.\n";
}
else{
echo "Failed to send Debug Report.\n";
}
}
}
?>
Ruben Barkow(mail-> at web dot de)
06-May-2004 05:32
06-May-2004 05:32
this does NOT work:
i tried to find out the name of a variable, that was sent to myfunction($in) with this code:
myfunction($in) {
$e=array_reverse(get_defined_vars());
echo "possible name for the variable in the function call: '";
foreach ($e as $n=>$v){
if ($v===$in) {
echo $n;
break;
}
}
echo"'";
}
but:
get_defined_vars() doesent give back the variables outside of a function.
(the code does work in the main programcode)
php - fw2 - net
29-Dec-2003 03:21
29-Dec-2003 03:21
biyectivo, above, is incorrect, at least as of PHP-4.3.3 which does indeed show variables from included/required files, as, IMO, it should. Very useful for debugging foreign code.
biyectivo at hotmail dot com
07-Jun-2003 04:16
07-Jun-2003 04:16
Thankfully, get_defined_vars() does NOT return variables which are assigned during an include() call. This would be a big security hole. For example:
//---------------------------------------------------------
include("foo.php");
$var1 = "Hi";
$vars = get_defined_vars();
$ks = array_keys($vars);
for ($i=0;$i<sizeof($ks);$i++)
{
echo $ks[$i]." --> ".$vars[$ks[$i]]."< br >";
}
//---------------------------------------------------------
will return all server variables, then
var1 --> Hi
but will NOT return
pwd --> MyPassword
even if inside foo.php there is a line stating
$pwd = "MyPassword";
jgettys at gnuvox dot com
22-Feb-2002 07:09
22-Feb-2002 07:09
Simple routine to convert a get_defined_vars object to XML.
function obj2xml($v, $indent='') {
while (list($key, $val) = each($v)) {
if ($key == '__attr') continue;
// Check for __attr
if (is_object($val->__attr)) {
while (list($key2, $val2) = each($val->__attr)) {
$attr .= " $key2=\"$val2\"";
}
}
else $attr = '';
if (is_array($val) || is_object($val)) {
print("$indent<$key$attr>\n");
obj2xml($val, $indent.' ');
print("$indent</$key>\n");
}
else print("$indent<$key$attr>$val</$key>\n");
}
}
//Example object
$x->name->first = "John";
$x->name->last = "Smith";
$x->arr['Fruit'] = 'Bannana';
$x->arr['Veg'] = 'Carrot';
$y->customer = $x;
$y->customer->__attr->id='176C4';
$z = get_defined_vars();
obj2xml($z['y']);
will output:
<customer id="176C4">
<name>
<first>John</first>
<last>Smith</last>
</name>
<arr>
<Fruit>Bannana</Fruit>
<Veg>Carrot</Veg>
</arr>
</customer>