最近写程序的时候发现一个这样的问题,一个if判断如下: [php] if (!empty(trim($ch_url))) { ... } [/php] 执行程序报出如下错误: [code] Fatal error: Can't use function return value in write context in ... [/code] 调整为如下形式则不报错误 [php] $ch_url = trim($ch_url); if (!empty($ch_url)) { ... } [/php…
方法简介: empty() This method removes not only child (and other descendant) elements, but also any text within the set of matched elements. This is because, according to the DOM specification, any string of text within an element is considered a child no…