php 数组去重

一维数组

 $aa=array("apple","banana","pear","apple","wail","watermalon"); $bb=array_unique($aa); print_r($bb);//Array ( [0] => apple [1] => banana [2] => pear [4] => wail [5] => watermalon

二维数组

1）因为某一键名的值不能重复，删除重复项

$aa = array(            array('id' => 123, 'name' => '张三'),            array('id' => 123, 'name' => '李四'),            array('id' => 124, 'name' => '王五'),            array('id' => 125, 'name' => '赵六'),            array('id' => 126, 'name' => '赵六')            );//需求，id 不能重复function assoc_unique($arr, $key){    $tmp_arr = array();        foreach($arr as $k => $v){            //搜索$v[$key]是否在$tmp_arr数组中存在，若存在返回true            if(in_array($v[$key], $tmp_arr)){                 unset($arr[$k]);            }else {                $tmp_arr[] = $v[$key];            }        }        sort($arr); //sort函数对数组进行排序        return $arr;}$key = 'id';assoc_unique(&$aa, $key);print_r($aa);//Array ( [0] => Array ( [id] => 123 [name] => 张三 ) [1] => Array ( [id] => 124 [name] => 王五 ) [2] => Array ( [id] => 125 [name] => 赵六 ) [3] => Array ( [id] => 126 [name] => 赵六 ) )

2）因内部的一维数组不能完全相同，而删除重复项

 $aa = array(            array('id' => 123, 'name' => '张三'),            array('id' => 123, 'name' => '李四'),            array('id' => 124, 'name' => '王五'),            array('id' => 123, 'name' => '李四'),            array('id' => 126, 'name' => '赵六')            );function array_unique_fb($array2D){                 foreach ($array2D as $v){                     $v = join(",",$v); //降维,也可以用implode,将一维数组转换为用逗号连接的字符串                     $temp[] = $v;                 }                 $temp = array_unique($temp);    //去掉重复的字符串,也就是重复的一维数组                foreach ($temp as $k => $v){                    $temp[$k] = explode(",",$v);   //再将拆开的数组重新组装                }                return $temp;            }            $bb=array_unique_fb($aa);            print_r($bb);            //Array ( [0] => Array ( [0] => 123 [1] => 张三 ) [1] => Array ( [0] => 123 [1] => 李四 ) [2] => Array ( [0] => 124 [1] => 王五 ) [4] => Array ( [0] => 126 [1] => 赵六 ) )