How to remove duplicates from php array

How to remove duplicates from PHP arrays: 1. Use the array_unique function to remove duplicates from PHP one-dimensional arrays; 2. Use the customized "function assoc_unique($arr, $key){...}" method Remove duplicates from php two-dimensional array.

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php array deduplication (one-dimensional array and two-dimensional array Dimensional array)

Removal of duplicate items in the array

Duplicate items in one-dimensional array:

Use The array_unique function is sufficient. The usage example is as follows:

The result is as follows:

Array ( [0] => apple [1] => banana [2] => pear [4] => wail [5] => watermalon ) 。

Duplicate items of two-dimensional array:

For two-dimensional array we The discussion is divided into two situations. One is to delete duplicates because the value of a certain key name cannot be repeated; the other is to delete duplicates because the internal one-dimensional array cannot be exactly the same. The following is an example:

一 Because the value of a certain button cannot be repeated, delete the repetitive item

 $v) { if(in_array($v[$key], $tmp_arr))//搜索$v[$key]是否在$tmp_arr数组中存在，若存在返回true { unset($arr[$k]); } else { $tmp_arr[] = $v[$key]; } } sort($arr); //sort函数对数组进行排序 return $arr; } $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') ); $key = 'id'; assoc_unique(&$aa, $key); print_r($aa); ?>

display result:

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 ) )

㈡ Because the internal one -dimensional array cannot be exactly the same, delete repeated items

 $v){ $temp[$k] = explode(",",$v); //再将拆开的数组重新组装 } return $temp; } $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') ); $bb=array_unique_fb($aa); print_r($bb) ?>

Display results:

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 ) )

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