yii2 - 如何将参数传递给 mainLayoutAsset.php 文件？

Question

我在 mainLayoutAsset.php 文件中有以下代码

<?php
/**
 * @link http://www.yiiframework.com/
 * @copyright Copyright (c) 2008 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

namespace frontend\assets;
use yii\web\AssetBundle;

/**
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @since 2.0
 */
class MainLayoutAsset extends AssetBundle
{
    public $basePath = '@webroot';
    public $baseUrl = '@web';
    public $css = [
    ];
    public $js = [
        'member-area/AdminLTE/app.js',
    ];
}

现在我想访问这个文件中的 params 文件参数

例如。

public $js = [
        'member-area/AdminLTE/app.js?v='.Yii::$app->params["version"],
     ]

但它给出了错误

PHP Parse Error – yii\base\ErrorException
syntax error, unexpected '.', expecting ']'

'js/tooltip.js?v='.Yii::$app->params["incFileVersion"],

Answer 1

来自关于类属性的 PHP 文档:

They are defined by using one of the keywords public, protected, or private, followed by a normal variable declaration. This declaration may include an initialization, but this initialization must be a constant value--that is, it must be able to be evaluated at compile time and must not depend on run-time information in order to be evaluated.

http://php.net/manual/en/language.oop5.properties.php

您可以简单地覆盖 init() :

public function init()
{
    parent::init();
    $this->js = [
        'member-area/AdminLTE/app.js?v=' . Yii::$app->params['version'],
    ];
}

你应该是 try this反而。