一、比较两个数组之差：array_diff 例如： $a1=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow"); $a2=array("e"=>"red","f"=>"green","g"=>"blue"); $result=array_diff($a1,$a2); print_r($result); 结果为：Array ( [d] => yellow )
二、比较两个数组的交集：array_intersect 例如： $a1=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"yellow"); $a2=array("e"=>"red","f"=>"green","g"=>"blue"); $result=array_intersect($a1,$a2); print_r($result); 结果为：Array ( [a] => red [b] => green [c] => blue )
三、取出数组中的那些数据：array_slice array_slice默认是不保留键名的。 使用array_slice函数要保留键名值，最后一个参数$preserve_keys设置为true即可。 例如： $levels = array('a' => 1, 'b' =>2, 'c' => 3, 'd' => 4, 'f' => 5, 'g' => 6); $firstLevels = array_slice($levels, 0, 5, true); 结果为： $firstLevels = array('a' => 1, 'b' =>2, 'c' => 3, 'd' => 4, 'f' => 5);
四、合并数组：array_merge() 例如： $a1=array("red","green"); $a2=array("blue","yellow"); print_r(array_merge($a1,$a2)); 结果为：Array ( [0] => red [1] => green [2] => blue [3] => yellow )
五、取出二维数组中的某个字段：array_column() 例如： $a = array( array( 'id' => 5698, 'first_name' => 'Peter', 'last_name' => 'Griffin', ), array( 'id' => 4767, 'first_name' => 'Ben', 'last_name' => 'Smith', ), array( 'id' => 3809, 'first_name' => 'Joe', 'last_name' => 'Doe', )
$last_names = array_column($a, 'last_name'); print_r($last_names);
结果为： Array ( [0] => Griffin [1] => Smith [2] => Doe )
六、将数组一维数组分成二维数组： array_chunk() 例如： $cars=array("Volvo","BMW","Toyota","Honda","Mercedes","Opel"); print_r(array_chunk($cars,2));
结果为： Array ( [0] => Array ( [0] => Volvo [1] => BMW ) [1] => Array ( [0] => Toyota [1] => Honda ) [2] => Array ( [0] => Mercedes [1] => Opel ) )
