如果将命名空间置于关系名称之前，将发生错误。

An error occurs when you prepend the namespace to the relationship name.

youdao

网域名称之前被惩罚过，或者是曾经是一个垃圾网站。

Domains previously used for spam or that are blacklisted.

youdao

为什么必须在listener属性中的方法名称之前加上“listener”前缀(看起来多余，是不是？)

Why do you have to preface the method name in the listener attribute with "listener" (it seems redundant, doesn't it)?

youdao