无法使用字符串键解压缩数组 [英] Cannot unpack array with string keys

问题描述

致命错误未捕获的错误:无法使用字符串键解压缩数组

FATAL ERROR Uncaught Error: Cannot unpack array with string keys

我知道我可以简单地两次运行方法fetch()并传递['q']和['bind']，但是我试图使用新的...来解压值.我想像这样传递值:

I know I can simply run the method fetch() twice and pass the ['q'] and ['bind'] but I am trying to get to grips with using the new ... to unpack values. I want to pass the values like so:

(string) SQL, (Array) Bind Values

但是我认为它试图从fetch()方法中解开绑定值数组以及响应数组.是否可以解压缩此数组(看起来像这样:)

But I think it tries to unpack the bind values array as well as the response array from the fetch() method. Is it possible to unpack this array (looks something like this:)

array(2) { 
    ["q"]=> string(7) "example" 
    ["bind"]=> array(1) {
        ["example"]=> string(3) "one"
    }
}

这是完整的代码，以防万一您需要了解它们如何组合在一起:

This is the whole code, in-case you need to see how it all fits together:

class ModelController {
    public static function execute($sql, $vals) {
        var_dump($vals);
    }
}

class ModelContainer {

    private $queries = [];

    public function add_model(Model $model, $name) {
        $this->queries[$name] = $model;
        return $this;
    }

    public function exec_all() {
        foreach($this->queries as $q) {
            ModelController::execute(...$q->fetch());
        }
    }

    public function exec($name) {

    }

}

class Model {

    private $sql;
    private $vals = [];


    public function set_q($statement) {
        $this->sql = $statement;
        return $this;
    }

    public function bind($vals = []) {
        $this->vals = $vals;
        return $this;
    }

    public function fetch() {
        return ['q' => (string)$this->sql,
            'bind' => $this->vals ];
    }
}

$m = new ModelContainer();
$m->add_model((new Model)->set_q('example sql here')->bind(['example' => 'example value here']), 'one');
$m->exec_all();

推荐答案

问题是"splat"运算符(数组拆包运算符或...)不适用于关联数组.示例:

The problem is that the "splat" operator (array unpacking operator or ...) does not work with associative arrays. Example:

$array = [1, 2, 3];
$assoc = ["one" => 1, "two" => 2, "three" => 3];

var_dump(...$array); //Works
var_dump(...$assoc); //Doesn't work

您需要强制对数组进行数字索引才能拆包.您可以使用 array_values :

You need to force an array to be numerically indexed in order to unpack it. You do this using array_values:

$values = array_values($q->fetch());
ModelController::execute(...$values);

数组值将确保所有值都有一个连续的数字键.

Array values will ensure all values have a sequential numeric key.

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