hidden_field
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hidden_field(object_name, method, options = {})
public
Works just like text_field, but returns an input tag of the "hidden" type instead.
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Value parameter
You can add a value to your hidden field by using the :value parameter.
Example
hidden_field(:object, :field, :value => params[:requestval])
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No security
One important thing to remember is that this is NOT hidden in the source code and can be modified by an evil user so all input in a hidden field should be considered as untrustworthy and checked just like a visible field.
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Hidden Field Example
Here’s a pseudo code example of a hidden field within an ERB template. A post has many comments and this comment form is in a post’s show view. This would set a comment’s post_id attribute.
<%= form_for(@comment) do |f| %>
<%= f.hidden_field :post_id, :value => @post.id %>
<% end %>