rails如何制作条件CLASS

AnA*_*ice 4 ruby-on-rails ruby-on-rails-3

<%=f.text_area :content, :class => 'grow'
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我希望这个课程有条件成为"成长"或"nogrow"

我试过了

<%=f.text_area :content, :class => grow ? "comment_content grow" : "nogrow"
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但那个错误.有任何想法吗?

Cha*_*rdy 6

这都是关于String Interpolation的.试试这个...

<%=f.text_area :content, :class => "#{grow ? 'comment_content grow' : 'nogrow'}" %>
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gun*_*unn 5

:class => grow ? "comment_content grow" : "nogrow"对我来说效果很好,你只需要结束这一行%>.我想你可以添加一些括号 - :class => (grow ? "comment_content grow" : "nogrow")无论如何更好的可读性.