$this->load->view('view_name',$data,TRUE); 是如何实现的？内部工作

Question

我知道这个方法有什么用了

查看方法的第三个参数 TRUE 或 FALSE 它在内部如何工作，因为想在核心 php 中创建相同的方法，这在核心 php 中非常有用。不仅在其他框架的核心中，还有蛋糕 php 等。

谢谢。

Answer 1

这是调用的主要函数：

public function view($view, $vars = array(), $return = FALSE)
{
    return $this->_ci_load(array('_ci_view' => $view, '_ci_vars' => $this->_ci_object_to_array($vars), '_ci_return' => $return));
}

现在第一个受保护函数_ci_load()

protected function _ci_load($_ci_data)
{
    // Set the default data variables
    foreach (array('_ci_view', '_ci_vars', '_ci_path', '_ci_return') as $_ci_val)
    {
        $$_ci_val = isset($_ci_data[$_ci_val]) ? $_ci_data[$_ci_val] : FALSE;
    }

    $file_exists = FALSE;

    // Set the path to the requested file
    if (is_string($_ci_path) && $_ci_path !== '')
    {
        $_ci_x = explode('/', $_ci_path);
        $_ci_file = end($_ci_x);
    }
    else
    {
        $_ci_ext = pathinfo($_ci_view, PATHINFO_EXTENSION);
        $_ci_file = ($_ci_ext === '') ? $_ci_view.'.php' : $_ci_view;

        foreach ($this->_ci_view_paths as $_ci_view_file => $cascade)
        {
            if (file_exists($_ci_view_file.$_ci_file))
            {
                $_ci_path = $_ci_view_file.$_ci_file;
                $file_exists = TRUE;
                break;
            }

            if ( ! $cascade)
            {
                break;
            }
        }
    }

    if ( ! $file_exists && ! file_exists($_ci_path))
    {
        show_error('Unable to load the requested file: '.$_ci_file);
    }

    // This allows anything loaded using $this->load (views, files, etc.)
    // to become accessible from within the Controller and Model functions.
    $_ci_CI =& get_instance();
    foreach (get_object_vars($_ci_CI) as $_ci_key => $_ci_var)
    {
        if ( ! isset($this->$_ci_key))
        {
            $this->$_ci_key =& $_ci_CI->$_ci_key;
        }
    }

    /*
     * Extract and cache variables
     *
     * You can either set variables using the dedicated $this->load->vars()
     * function or via the second parameter of this function. We'll merge
     * the two types and cache them so that views that are embedded within
     * other views can have access to these variables.
     */
    if (is_array($_ci_vars))
    {
        foreach (array_keys($_ci_vars) as $key)
        {
            if (strncmp($key, '_ci_', 4) === 0)
            {
                unset($_ci_vars[$key]);
            }
        }

        $this->_ci_cached_vars = array_merge($this->_ci_cached_vars, $_ci_vars);
    }
    extract($this->_ci_cached_vars);

    /*
     * Buffer the output
     *
     * We buffer the output for two reasons:
     * 1. Speed. You get a significant speed boost.
     * 2. So that the final rendered template can be post-processed by
     *  the output class. Why do we need post processing? For one thing,
     *  in order to show the elapsed page load time. Unless we can
     *  intercept the content right before it's sent to the browser and
     *  then stop the timer it won't be accurate.
     */
    ob_start();

    // If the PHP installation does not support short tags we'll
    // do a little string replacement, changing the short tags
    // to standard PHP echo statements.
    if ( ! is_php('5.4') && ! ini_get('short_open_tag') && config_item('rewrite_short_tags') === TRUE)
    {
        echo eval('?>'.preg_replace('/;*\s*\?>/', '; ?>', str_replace('<?=', '<?php echo ', file_get_contents($_ci_path))));
    }
    else
    {
        include($_ci_path); // include() vs include_once() allows for multiple views with the same name
    }

    log_message('info', 'File loaded: '.$_ci_path);

    // Return the file data if requested
    if ($_ci_return === TRUE)
    {
        $buffer = ob_get_contents();
        @ob_end_clean();
        return $buffer;
    }

    /*
     * Flush the buffer... or buff the flusher?
     *
     * In order to permit views to be nested within
     * other views, we need to flush the content back out whenever
     * we are beyond the first level of output buffering so that
     * it can be seen and included properly by the first included
     * template and any subsequent ones. Oy!
     */
    if (ob_get_level() > $this->_ci_ob_level + 1)
    {
        ob_end_flush();
    }
    else
    {
        $_ci_CI->output->append_output(ob_get_contents());
        @ob_end_clean();
    }

    return $this;
}

第二个受保护函数 _ci_object_to_array :

protected function _ci_object_to_array($object)
{
    return is_object($object) ? get_object_vars($object) : $object;
}

就是这样。如果你了解你的 php，你可以很容易地弄清楚它的作用:)干杯