php数组对数组元素去重

<?php
$arr = array("a"=>"a1","b"=>'b1',"c"=>"a2","d"=>"a1");
$arr1 = array_flip($arr);
print_r($arr1);//先反转一次,去掉重复值,输出Array ( [a1] => d [b1] => b [a2] => c )
$arr2 = array_flip($arr);
print_r($arr2);//再反转回来,得到去重后的数组,输出Array ( [a1] => d [b1] => b [a2] => c )
$arr3 = array_unique($arr);
print_r($arr3);//利用php的array_unique函数去重,输出Array ( [a] => a1 [b] => b1 [c] => a2 )
?>

<?php
function assoc_unique($arr, $key) {
 $tmp_arr = array();
 foreach($arr as $k => $v) {
  if(in_array($v[$key], $tmp_arr)) {
   unset($arr[$k]);
  } else {
   $tmp_arr[] = $v[$key];
  }
 }
 sort($arr);
 return $arr;
}

$aa = array(
 array('id' => 123, 'name' => '淡淡清香弥漫世界'),
 array('id' => 123, 'name' => '螃蟹'),
 array('id' => 124, 'name' => '前端开发者'),
 array('id' => 125, 'name' => '螃蟹'),
 array('id' => 126, 'name' => 'HTML5研究者')
);
$key = 'name';
assoc_unique(&$aa, $key);
print_r($aa);
?>

SELECT arc.*,tp.typedir,tp.typename,tp.corank,tp.isdefault,tp.defaultname,tp.namerule,

tp.namerule2,tp.ispart,tp.moresite,tp.siteurl,tp.sitepath
FROM `dede_archives` arc LEFT JOIN `dede_arctype` tp ON arc.typeid=tp.id WHERE arc.typeid IN (29) AND

arc.arcrank > -1 ORDER BY arc.sortrank DESC

{dede:arclist orderby=’weight’ typeid=’29′ isweight=’y’

limit=’4,1′ titlelen=’100′ infolen=’100′ }

else if($orderby ==

‘weight’) $ordersql = ” order by arc.weight asc”;

{dede:list pagesize='10' titlelen='50' orderby='weight'} •[field:textlink/]<br/> {/dede:list}

else if($orderby=="weight") {     $ordersql = " order by arc.weight $orderWay"; }

if(ereg('hot|click|weight|lastpost',$orderby))

{dede:arclist row='10' titlelen='50' orderby='weight'} •[field:textlink/]<br/> {/dede:arclist}

〈?php
         echo date(’Y-m-d H:i:s’);
  ?〉

<?php 
if(isset($_FILES['file'])){ 
$upload='upload/'.$_FILES['file']['name']; 

if(is_uploaded_file($_FILES['file']['tmp_name'])){ 

//iconv函数解决上传文件中文名乱码的问题，但是不提倡文件名是中文的，特别是unix/linux环境下 ,当你要输出的时候，又要给变回来，iconv('gb2312',UTF-8',$upload)

if(!move_uploaded_file($_FILES['file']['tmp_name'],iconv('UTF-8','gb2312',$upload))){ 

echo 'failed'; 

}else{ 
echo 'success'; 

} 
} 
else{ 
echo 'failed'; 

} 

} 
?> 

/******关于iconv函数的应用：string iconv ( string in_charset, string out_charset, string str )
* in_charset：传入的文件的格式

* out_charset：输出的文件的格式

* str：文件路径

*****/