Ruby-on-rails rails erb 表单助手 options_for_select :selected
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rails erb form helper options_for_select :selected
提问by Drew Harris
I have an edit form in erb.
我在 erb 中有一个编辑表单。
<%= form_for @animal do |f| %>
Within the code I have a select with options:
在代码中，我有一个带有选项的选择：
<%= f.select :gender, options_for_select([['Mare'], ['Stallion'], ['Gelding']], :selected => :gender) %>
However, the select is not showing the correct selected value. What could I be doing wrong? I can get it to work if I hardcode it but of course that is not a viable option.
但是，选择未显示正确的选定值。我可能做错了什么？如果我对它进行硬编码，我可以让它工作，但这当然不是一个可行的选择。
回答by kristinalim
In your code, your options_for_select()call sets the selected value to "gender" and does not attempt to use the value from your form object.
在您的代码中，您的options_for_select()调用将所选值设置为“性别”，并且不会尝试使用表单对象中的值。
Please see the docs for options_for_select()for usage examples.
options_for_select()有关使用示例，请参阅文档。
options_for_select(['Mare', 'Stallion', 'Gelding'], f.object.gender)
options_for_select(['Mare', 'Stallion', 'Gelding'], :selected => f.object.gender)
Alternatively, you can do this, which will already use the gender()value for your form object:
或者，您可以这样做，这将已经使用gender()表单对象的值：
<%= f.select :gender, ['Mare', 'Stallion', 'Gelding'] %>
回答by Hans Hauge
By the way, if you are using :include_blank => true, this will set your current selection to blank even though the form "knows" what is selected.
顺便说一句，如果您正在使用:include_blank => true，即使表单“知道”选择了什么，这也会将您当前的选择设置为空白。
