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<?php
$a = 'hello';
?>
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$$a = 'world';
?>
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<?php
echo "$a ${$a}";
?>
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<?php
echo "$a $hello";
?>
å®ä»¬é½ä¼è¾åºï¼hello worldã
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须解å³ä¸ä¸ªæ¨¡æ£±ä¸¤å¯çé®é¢ãè¿å°±æ¯å½åä¸ $$a[1] æ¶ï¼è§£æå¨éè¦ç¥éæ¯æ³è¦ $a[1]ä½ä¸ºä¸ä¸ªåéå¢ï¼è¿æ¯æ³è¦ $$a ä½ä¸ºä¸ä¸ªåé并ååºè¯¥åéä¸ç´¢å¼ä¸º [1] çå¼ã解å³æ¤é®é¢çè¯æ³æ¯ï¼å¯¹ç¬¬ä¸ç§æ
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å«æéæ³å符æ¶ï¼ä¾å¦æ¥èª json_decode() æ SimpleXMLï¼ã
Example #1 å¯åå±æ§ç¤ºä¾
<?php
class foo {
var $bar = 'I am bar.';
var $arr = array('I am A.', 'I am B.', 'I am C.');
var $r = 'I am r.';
}
$foo = new foo();
$bar = 'bar';
$baz = array('foo', 'bar', 'baz', 'quux');
echo $foo->$bar . "\n";
echo $foo->$baz[1] . "\n";
$start = 'b';
$end = 'ar';
echo $foo->{$start . $end} . "\n";
$arr = 'arr';
echo $foo->$arr[1] . "\n";
echo $foo->{$arr}[1] . "\n";
?>
以ä¸ä¾ç¨ä¼è¾åºï¼
I am bar.
I am bar.
I am bar.
I am r.
I am B.
Warning
注æï¼å¨ PHP çå½æ°åç±»çæ¹æ³ä¸ï¼è¶
å
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