Note: String must be inside “double quotes”
<%= f.text_area :address, placeholder:"Street\r\nCity\r\nState, Zip"
This style of multi-line placeholder works fine in safari, Google Chrome and Browsers derived from Google Chrome. How ever this is not the case in firefox and IE. So have multi-line placeholders in these browser we have to use the JS way.
There is a jQuery plugin to do this job. Luckly, RubyOnRails’s gem for this plugin is also avilable here
or you can use the jQuery plugin itself