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ini_get

(PHP 4, PHP 5)

ini_get获取一个配置选项的值

说明

string ini_get ( string $varname )

成功时返回配置选项的值。

参数

varname

配置选项名称。

返回值

成功是返回配置选项值的字符串,null 的值则返回空字符串。如果配置选项不存在,将会返回 FALSE

范例

Example #1 一些 ini_get() 例子

<?php
/*
我们的 php.ini 包含了以下的设置:

display_errors = On
register_globals = Off
post_max_size = 8M
*/

echo 'display_errors = ' ini_get('display_errors') . "\n";
echo 
'register_globals = ' ini_get('register_globals') . "\n";
echo 
'post_max_size = ' ini_get('post_max_size') . "\n";
echo 
'post_max_size+1 = ' . (ini_get('post_max_size')+1) . "\n";
echo 
'post_max_size in bytes = ' return_bytes(ini_get('post_max_size'));

function 
return_bytes($val) {
    
$val trim($val);
    
$last strtolower($val[strlen($val)-1]);
    switch(
$last) {
        
// 自 PHP 5.1.0 起可以使用修饰符 'G'
        
case 'g':
            
$val *= 1024;
        case 
'm':
            
$val *= 1024;
        case 
'k':
            
$val *= 1024;
    }

    return 
$val;
}

?>

以上例程的输出类似于:


display_errors = 1
register_globals = 0
post_max_size = 8M
post_max_size+1 = 9
post_max_size in bytes = 8388608

注释

Note: 当查询一个 boolean 值

一个 off 的 boolean ini 值将会以空字符串或者 "0" 返回;on 的 ini 值会以 "1" 返回。 此函数也会返回 INI 值的文字字符串。

Note: 当查询一个内存尺寸的值

许多内存尺寸的 ini 值,类似 upload_max_filesize 是以简写表示法储存在 php.ini 文件里。 ini_get() 会返回 php.ini 文件中储存的确切字符串,而不是它的等量 integer。 尝试对这些值使用常规算术运算函数将不会得到预期的结果。 以上例子显示了转换简写表示法为字节的一种方式,和 PHP 源码所做的比较像。

更新日志

版本 说明
5.3.0 当配置项不存在,之前会返回空字符串,现在会返回 FALSE

参见

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User Contributed Notes 7 notes

up
11
Stas Trefilov, OpteamIS
5 years ago
another version of return_bytes which returns faster and does not use multiple multiplications (sorry:). even if it is resolved at compile time it is not a good practice;
no local variables are allocated;
the trim() is omitted (php already trimmed values when reading php.ini file);
strtolower() is replaced by second case which wins us one more function call for the price of doubling the number of cases to process (may slower the worst-case scenario when ariving to default: takes six comparisons instead of three comparisons and a function call);
cases are ordered by most frequent goes first (uppercase M-values being the default sizes);
specs say we must handle integer sizes so float values are converted to integers and 0.8G becomes 0;
'Gb', 'Mb', 'Kb' shorthand byte options are not implemented since are not in specs, see
http://www.php.net/manual/en/faq.using.php#faq.using.shorthandbytes

<?php
function return_bytes ($size_str)
{
    switch (
substr ($size_str, -1))
    {
        case
'M': case 'm': return (int)$size_str * 1048576;
        case
'K': case 'k': return (int)$size_str * 1024;
        case
'G': case 'g': return (int)$size_str * 1073741824;
        default: return
$size_str;
    }
}
?>
up
3
peter
6 years ago
The above example function called return_bytes() assumes that ini_get('upload_max_filesize') delivers only one letter at the end. As I've seen 'Mb' and things like that, I'd suggest to change the $last = ... part into $last = strtolower(substr($val,strlen($val/1),1)).
I'd call it $unit then.
up
2
david dot tulloh at infaze dot com dot au
10 years ago
You can set custom entries in the ini file to provide globals such as database details.
However these must be retrieved with get_cfg_var, ini_get won't work.
up
3
Ivo Mandalski
3 years ago
This version of return_bytes takes care of the MB, GB, KB cases along with the M,G,K ones.
Hope this is helpful!

<?php
   
public static function return_bytes ($val)
    {
        if(empty(
$val))return 0;

       
$val = trim($val);

       
preg_match('#([0-9]+)[\s]*([a-z]+)#i', $val, $matches);

       
$last = '';
        if(isset(
$matches[2])){
           
$last = $matches[2];
        }

        if(isset(
$matches[1])){
           
$val = (int) $matches[1];
        }

        switch (
strtolower($last))
        {
            case
'g':
            case
'gb':
               
$val *= 1024;
            case
'm':
            case
'mb':
               
$val *= 1024;
            case
'k':
            case
'kb':
               
$val *= 1024;
        }

        return (int)
$val;
    }
?>
up
2
filh at filh dot org
9 years ago
Concerning the value retourned, it depends on how you set it.
I had the problem with horde-3 which test the safe_mode value.
THan :
- if you set the value with php_admin_value safe_mode Off (or On) ini_get returns the string
- if you set the value with php_admin_flag safe_mode Off (or On) ini_get returns the boolean.
up
2
Der Graph
10 years ago
It might be useful for included scripts that include other files to extend the 'include_path' variable:

<?php ini_set('include_path',ini_get('include_path').':../includes:');  ?>

Sometimes, it may also be useful to store the current 'include_path' in a variable, overwrite it, include, and then restore the old 'include_path'.
up
0
nicolas dot grekas+php at gmail dot com
5 years ago
Here is how to accurately test for boolean php.ini values:

<?php

function ini_get_bool($a)
{
   
$b = ini_get($a);

    switch (
strtolower($b))
    {
    case
'on':
    case
'yes':
    case
'true':
        return
'assert.active' !== $a;

    case
'stdout':
    case
'stderr':
        return
'display_errors' === $a;

    default:
        return (bool) (int)
$b;
    }
}

?>
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