Webmaster Forum / Flash / Flash Site Design / June 2007

simey70,

   The addition operator, +, is a concatenator for strings.  That means it
combines two or more strings into a single string.  The word "cat", for
example can be presented as the three letters that comprise it, or like
this:  "c" + "at" -- or also this: "ca" + "t"; or "c" + "a" + "t".  (When
the addition operator is used with numbers, it adds them, like the familiar
1 + 2 = 3.)

   So in the line of code you've shown, the letter "s" is being
concatenated (added) to some other string.  What other string?  Well, that
string is stored in an arbitrarily named variable, link.  This variable
exists in a specific location (the main timeline), which can be addressed as
_root.  So the full expression "s" + _root.link means "Combine 's' with the
value of the link variable, which is located in the _root."  The result, of
course, depends on the value of link.

   As Franz said, if the value of link happens to be "SomeString", then
gotoAndPlay() is being asked to go to the frame whose label reads
"sSomeString" and play from that point.

David Stiller
Co-author, Foundation Flash CS3 for Designers
http://tinyurl.com/2k29mj
"Luck is the residue of good design."