EnterAction Should allow appending text before the new line as well.

What I want to do is when a user press enter in the middle of a string to break it into two lines and concat the string with +

eg:

convert this,

string s = "Press enter here -> <- there"

to

string s = "Press enter here ->" 
    + " <- there"

But I can only append + " to the string below. No way to add " to the string above :(