范围：使用函数中定义的变量 [英] Scope: Using Variable Defined in a Function

问题描述

我在函数.php文件中定义了某些变量：

  add_action（'the_post'，'paginate_slide '）; 
 
函数paginate_slide（$ post）{
 
全局$ pages，$ multipage，$ numpages; $（）
 $ b if（is_single（）&&; get_post_type（）=='post'）{
 
 $ multipage = 1; 
 $ id = get_the_ID（）; 
 $ custom = array（）; 
 $ pages = array（）; 
 $ i = 1; 
 
 foreach（get_post_custom_keys（）as $ key）
 if（false！== strpos（$ key，'slide'））
 $ custom [$ key] = get_post_meta（ $ id，$ key，true）; 
 
 while（isset（$ custom [slide {$ i} -title]））{
 
 $ page =''; 
 $ tzTitle = $ custom [slide {$ i} -title]; 
 $ tzImage = $ custom [slide {$ i} -image]; 
 $ tzDesc = $ custom [slide {$ i} -desc]; 
 $ tzEmbed = $ custom [slide {$ i} -embed]; 
 
 $ page =< h2> {$ tzTitle}< / h2>< img src ='{$ tzImage}'/>; 
 $ pages [] = $ page; 
 $ i ++; 
} 
 
 $ numpages = count（$ pages）; 
} 
} 
  

我想输出一些这些变量像这样的template.php文件：<？php echo $ tzDesc; ？> 但我似乎无法让它工作。根据我对变量作用域的理解，为了调用这些变量在另一个地方，我需要在全局范围内定义它们，并将它们称为全局函数，就像我做了 $ pages，$ multipage，$ numpages; 一样。这应该允许我将这些变量插入到我需要的地方。问题是当我将它们从函数中取出并在全局范围内定义它们时，整个函数停止工作。

如何构造这个结构，以便我可以调用<？php echo $ tzDesc; ？> 在网站的任何地方，并让它回声定义的信息？

我不知道这是否重要，但这是一个如果你想使用<？php echo $ tzDesc;

？>> 无论如何，您需要将 $ tzDesc 定义为全局变量。但是，我不建议这样做，因为全局变量被认为是很差的编程习惯。

更好的解决方案是将 paginate_slide（）添加 $ tzDesc （以及其他值）到 $ post 对象。这样，只要您调用 the_post（），就可以访问这些变量。如果你走这条路线，一定要命名空间变量：

  $ post-> ns_tzDesc = $ tzDesc; 
  

I have a function in a functions.php file that defines certain variables:

add_action( 'the_post', 'paginate_slide' );

function paginate_slide( $post ) {

    global $pages, $multipage, $numpages;

    if( is_single() && get_post_type() == 'post' ) {

    $multipage = 1;
    $id = get_the_ID();
    $custom = array();
    $pages = array();
    $i = 1;

    foreach( get_post_custom_keys() as $key )
        if ( false !== strpos( $key, 'slide' ) )
            $custom[$key] = get_post_meta( $id, $key, true);

    while( isset( $custom["slide{$i}-title"] ) ) {

        $page = '';
        $tzTitle = $custom["slide{$i}-title"];
        $tzImage = $custom["slide{$i}-image"];
        $tzDesc = $custom["slide{$i}-desc"];
        $tzEmbed = $custom["slide{$i}-embed"];

        $page = "<h2>{$tzTitle}</h2><img src='{$tzImage}' />";
        $pages[] = $page;
        $i++;
    }

    $numpages = count( $pages );
    }
}

I'd like to output some of these variables in a template.php file like so: <?php echo $tzDesc; ?> but I can't seem to get it to work. From what I understand about the variables scope, in order to call these variables in another place I need to define them within the global scope and call them as global in this function like I did the $pages, $multipage, $numpages;. That should allow me to plug those variables in where I need them. The problem is when I take them out of the function and define them above within the global scope the entire function stops working.

How do I need to structure this so I can call <?php echo $tzDesc; ?> anywhere in the site and have it echo the defined info?

I don't know if this matters but this is on a WordPress site.

解决方案

If you want to use <?php echo $tzDesc; ?> anyway, you would need to define $tzDesc as a global variable. However, I don't recommend doing so as global variables are considered poor programming practice.

A better solution would be to have the paginate_slide() add $tzDesc (and other values) to the $post object. That way you have access to these variables anytime you call the_post(). If you go this route, be sure to namespace you variables:

$post->ns_tzDesc = $tzDesc;

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