【错误详情】:Fatal error: Can't use function return value in write context in ……
【错误经过】: 来看这么一段程序
[php] view plain copy print ?
$value = $_POST['username']; if (empty(trim($value))){ echoError('请输入用户名!'); }
乍一看上去很简单,没什么问题,可经过异常排查后确定就是这一小段程序出现了上面的Fatal error~,于是首先怀疑自定义方法echoError的实现存在什么问题,可经过排查后问题不是出在这里,十分不解,最后经过查询手册发现empty()方法在最后有这么一小段解释:
Note: empty() 只检测变量,检测任何非变量的东西都将导致解析错误。换句话说,后边的语句将不会起作用: empty(addslashes($name))。
明白了~ 程序结构改变:
[php] view plain copy print ?
$value = trim($_POST['username']); if (empty($value)){ echoError('请输入用户名!'); }

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