PHP中array_multisort函数对多个数组或多维数组进行排序,参数数组被当成一个表的列并以行来排序——这类似于 SQL 的 ORDER BY 子句的功能。第一个数组是要排序的主要数组。数组中的行(值)比较为相同的话就按照下一个输入数组中相应值的大小来排序,依此类推。注意:作为参数的数组元素个数应保持一致,否则会报错。
先看一个对多个数组进行排序的例子。
$array1 = array('one'=>'10','two'=>'20','three'=>'20','four'=>10);
$array2 = array('one'=>'10','two'=>'30','three'=>'20','four'=>'1');
$array3 = array('one'=>'C','two'=>'A','three'=>'B','four'=>'F');
array_multisort($array1,$array2,$array3);
print_r($array1);//Array ( [four] => 10 [one] => 10 [three] => 20 [two] => 20 )
print_r($array2);//Array ( [four] => 1 [one] => 10 [three] => 20 [two] => 30 )
print_r($array3);//Array ( [four] => F [one] => C [three] => B [two] => A )
在看一个,改变排序顺序的例子。
$array1 = array('one'=>'10','two'=>'20','three'=>'20','four'=>10);
$array2 = array('one'=>'10','two'=>'30','three'=>'20','four'=>'1');
$array3 = array('one'=>'C','two'=>'A','three'=>'B','four'=>'F');
array_multisort($array1,SORT_DESC,$array2,SORT_ASC,$array3);
print_r($array1);//Array ( [three] => 20 [two] => 20 [four] => 10 [one] => 10 )
print_r($array2);//Array ( [three] => 20 [two] => 30 [four] => 1 [one] => 10 )
print_r($array3);//Array ( [three] => B [two] => A [four] => F [one] => C )
在这个例子中,第一个数组降序排序,碰到相同的值,按照第二个数组升序值进行排序。
注意:如果要是排序数组都是关联数组,则保留原有key名,若存在索引数组,则会按顺序重新建立索引。
$array1 = array('one'=>'10',2=>'20',3=>'20',4=>10);
$array2 = array('one'=>'10','2'=>'30','3'=>'20','four'=>'1');
$array3 = array('one'=>'C','2'=>'A','3'=>'B','four'=>'F');
array_multisort($array1,$array2,$array3);
print_r($array1); //Array ( [0] => 10 [one] => 10 [1] => 20 [2] => 20 )
print_r($array2); //Array ( [four] => 1 [one] => 10 [0] => 20 [1] => 30 )
print_r($array3); //Array ( [four] => F [one] => C [0] => B [1] => A )
多维数组排序。
我们通常有一些多维数组需要排序:
$guys = array(
array('name'=>'jake', 'score'=>80, 'grade' =>'A'),
array('name'=>'jina', 'score'=>70, 'grade'=>'A'),
array('name'=>'john', 'score'=>70, 'grade' =>'A'),
array('name'=>'ben', 'score'=>20, 'grade'=>'B')
);
//例如我们想按成绩倒序排列,如果成绩相同就按名字的升序排列。
//这时我们就需要根据$guys的顺序多弄两个数组出来:
$scores = array(80,70,70,20);
$names = array('jake','jina','john','ben');
//然后
array_multisort($scores, SORT_DESC, $names, $guys);
foreach($guys as $v){
print_r($v);
echo "
";
}
/*
Array ( [name] => jake [score] => 80 [grade] => A )
Array ( [name] => jina [score] => 70 [grade] => A )
Array ( [name] => john [score] => 70 [grade] => A )
Array ( [name] => ben [score] => 20 [grade] => B )
*/