在我的数据库中,我有一个拥有外国钥匙的领域。 有时,这些数值为NUL或0。
我知道这个助手的空白? 如果实地存在一些规定,是否有类似的情况? 由于空白不在这里工作。
这一观点的法典就是这样。
<%= @b.author unless @b.author_id.blank? %>
在我的数据库中,我有一个拥有外国钥匙的领域。 有时,这些数值为NUL或0。
我知道这个助手的空白? 如果实地存在一些规定,是否有类似的情况? 由于空白不在这里工作。
这一观点的法典就是这样。
<%= @b.author unless @b.author_id.blank? %>
页: 1
def identified? author
author.id.blank? or author.id == 0
end
你们可以尝试:
<% if @b.author_id == 0 %>
#display something here
<% else %>
#display something else
<% end %>
你的看法。
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