按对象字段对对象数组进行排序

问题描述：

如何按其中一个字段(例如 name 或 count )对对象数组进行排序?

How can I sort this array of objects by one of its fields, like name or count ?

  Array
(
    [0] => stdClass Object
        (
            [ID] => 1
            [name] => Mary Jane
            [count] => 420
        )

    [1] => stdClass Object
        (
            [ID] => 2
            [name] => Johnny
            [count] => 234
        )

    [2] => stdClass Object
        (
            [ID] => 3
            [name] => Kathy
            [count] => 4354
        )

   ....

答

使用 usort，这里有一个改编自手册的例子:

Use usort, here's an example adapted from the manual:

function cmp($a, $b) {
    return strcmp($a->name, $b->name);
}

usort($your_data, "cmp");

您还可以使用任何 callable 作为第二个参数.以下是一些示例:

You can also use any callable as the second argument. Here are some examples:

使用匿名函数(来自 PHP 5.3)

Using anonymous functions (from PHP 5.3)

  usort($your_data, function($a, $b) {return strcmp($a->name, $b->name);});

从班级内部

From inside a class

  usort($your_data, array($this, "cmp")); // "cmp" should be a method in the class

使用箭头函数(来自 PHP 7.4)

Using arrow functions (from PHP 7.4)

  usort($your_data, fn($a, $b) => strcmp($a->name, $b->name));

此外，如果您要比较数值，fn($a, $b) =>$a->count - $b->count 作为比较"函数应该可以解决问题，或者，如果您想要另一种方式来做同样的事情，从 PHP 7 开始，您可以使用 Spaceship operator，像这样:fn($a, $b) =>$a->count ;$b->count.

Also, if you're comparing numeric values, fn($a, $b) => $a->count - $b->count as the "compare" function should do the trick, or, if you want yet another way of doing the same thing, starting from PHP 7 you can use the Spaceship operator, like this: fn($a, $b) => $a->count <=> $b->count.

按对象字段对对象数组进行排序

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