解决方法
您可能对TextHelper的
truncate功能感兴趣：
truncate("Once upon a time in a world far far away")
# => Once upon a time in a world f...
truncate("Once upon a time in a world far far away",:length => 14)
# => Once upon a...
truncate("And they found that many people were sleeping better.",:length => 25,"(clipped)")
# => And they found that many (clipped)
truncate("And they found that many people were sleeping better.",:omission => "... (continued)",:length => 15)
# => And they found... (continued)