按特定值对多维数组进行排序(使用asort和rasort)

Question

我意识到还有几个与此相关的问题--但要么它们对我来说毫无意义，要么就不符合我的需要。

我有一个数组，可以通过使用asort()和arsort()按字母顺序对第一个值进行排序。我的多维数组的一个例子可能是：

[{"Name":"Amber","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Bob","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Hans","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Jeff","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Michael","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0}]

通过使用asort()和arsort()，它按照"Name"字母顺序或反向字母顺序排序。现在，我需要同样的功能，只基于"dealType"。

我尝试过一些已经张贴在Stackoverflow上的例子，但我必须误解它们，因为它们不起作用。我怎样才能做到这一点？

编辑乔纳森给出了字母排序的正确答案，但略作修改：

//the custom function to do our sort
function cmp($a,$b){
    //get which string is less or 0 if both are the same
    $cmp = strcasecmp($a->dealType, $b->dealType);
    //if the strings are the same, check name
    return $cmp;
}
//sort using a custom function
usort($obj, 'cmp');

下面的代码用于按字母顺序进行反向排序：

//the custom function to do our sort
function cmp($a,$b){
    //get which string is less or 0 if both are the same
    $cmp = strcasecmp($b->dealType, $a->dealType);
    //if the strings are the same, check name
    return $cmp;
}
//sort using a custom function
usort($obj, 'cmp');

Answer 1

您应该使用乌斯托，这将允许您使用自定义的比较函数来确定排序时哪个值放在第一位。

类似于：

<?php
//the data you supplied. normally just an array
$data = array ( 0 => array ( 'Name' => 'Amber', 'date' => '', 'dealType' => 'deal1', 'id' => '***@***.com', 'registered' => 0, ), 1 => array ( 'Name' => 'Bob', 'date' => '', 'dealType' => 'deal5', 'id' => '***@***.com', 'registered' => 0, ), 2 => array ( 'Name' => 'Hans', 'date' => '', 'dealType' => 'deal3', 'id' => '***@***.com', 'registered' => 0, ), 3 => array ( 'Name' => 'Jeff', 'date' => '', 'dealType' => 'deal2', 'id' => '***@***.com', 'registered' => 0, ), 4 => array ( 'Name' => 'Michael', 'date' => '', 'dealType' => 'deal1', 'id' => '***@***.com', 'registered' => 0, ), );

//show what we got going into sort
echo '<pre>'.print_r($data, 1).'</pre>';

function cmp($a,$b){
    //get which string is less or 0 if both are the same
    $cmp = strcasecmp($a['dealType'], $b['dealType']);
    //if the strings are the same, check name
    if($cmp == 0){
        //compare the name
        $cmp = strcasecmp($a['Name'], $b['Name']);
    }
    return $cmp;
}
//sort using a custom function
usort($data, 'cmp');

//show what we got after sort
echo '<pre>'.print_r($data, 1).'</pre>';
?>

这将首先在dealType上排序，然后在Name上排序，如果dealType是相同的话。如果要进行反向排序，则可以在$a调用中交换strcasecmp()和$b的顺序。

编辑:这些数据很可能是从数据库中提取出来的。如果是这样的话，那么只需ORDER BY列。你可以像SELECT * FROM table ORDER BY dealType ASC,Name ASC那样做

Edit2:更新代码以避免使用匿名函数。此外，还可以查看在意为中工作的代码。

Answer 2

如果我正确地理解了您的问题，您就有数组(例如A)数组(例如B)，并且您希望根据它们中的某些值对B进行排序。如果是这样的话，我以前也遇到过同样的问题，并创建了名为line_sort的自定义函数。如果需要，可以通过下面的示例使用它：

$array=json_decode('[{"Name":"Amber","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Bob","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Hans","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Jeff","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0},{"Name":"Michael","date":"","dealType":"B-Braun Medical, Inc.","id":"***@***.com","registered":0}]');
$array=line_sort("dealType",$array);

第一个值是要排序的关键，第二个是要排序的数组，下面是函数代码(抱歉，它不是英文)：

function line_sort($klic,$hodnoty)
{
  if (!is_array($hodnoty))
  {
    trigger_error("Second parameter has to be multidimensional array", E_USER_WARNING );
    return;
  }
  for ($x=0;$x<count($hodnoty)-1;$x++)
  {
    for ($y=count($hodnoty)-1;$y>=$x;$y--)
    {
      $radek1=$hodnoty[$y];
      $radek2=$hodnoty[$y+1];
      if ((isset($radek1[$klic]) && isset($radek2[$klic])) && (intval($radek1[$klic]) > intval($radek2[$klic])) || (isset($radek2[$klic]) && !isset($radek1[$klic])))
      {
        $hodnoty[$y]=$radek2;
        $hodnoty[$y+1]=$radek1;
        continue;
      }
      else if((isset($radek1[$klic]) && isset($radek2[$klic])) && (intval($radek1[$klic]) == intval($radek2[$klic])))
      {
        if (strcmp($radek1[$klic],$radek2[$klic])>0)
        {
          $hodnoty[$y]=$radek2;
          $hodnoty[$y+1]=$radek1;
        }
      }
    }
  }
  return $hodnoty;
}

如果您希望看到此函数的输出示例，请查看以下内容：http://test.hanzlsoft.eu/

Answer 3

我相信你在找array_multisort()：http://php.net/manual/en/function.array-multisort.php

示例：

<?php
$ar = array(
       array("10", 11, 100, 100, "a"),
       array(   1,  2, "2",   3,   1)
      );
array_multisort($ar[0], SORT_ASC, SORT_STRING,
                $ar[1], SORT_NUMERIC, SORT_DESC);
var_dump($ar);
?>

来源：http://php.net/manual/en/function.array-multisort.php#example-4558