标准翻译"名称只能由字母数字和下划线”_”组成."
问题描述:
标准翻译"名称只能由字母数字和下划线”_”组成."
名称只能由字母数字和下划线”_”组成,且首字母不能为下划线.
答
User name can only be made up by numbers,letters and "_",what's more,"_" can not be the beginning.