Searching for marked (selected) text in Emacs

Question

I use emacs for viewing and editing code and other text files. I wanted to know if there is a way to search forward or backward for text which is marked in the current buffer. S

Answer 1

I am using the following which does not have the problem of having to type more then one successive C-s to find later occurences:

    (defun search-selection (beg end)
      "search for selected text"
      (interactive "r")
      (kill-ring-save beg end)
      (isearch-mode t nil nil nil)
      (isearch-yank-pop)
    )
    (define-key global-map (kbd "<C-f3>") 'search-selection)

The disadvantage of the previous code is that the selected text is copied to the stretch. The following code does not have this problem:

    (defun search-selection (beg end)
      "search for selected text"
      (interactive "r")
      (let (
            (selection (buffer-substring-no-properties beg end))
           )
        (deactivate-mark)
        (isearch-mode t nil nil nil)
        (isearch-yank-string selection)
      )
    )
    (define-key global-map (kbd "<C-f3>") 'search-selection)

Answer 2

The answers above (including the accepted one) are too cumbersome IMHO. I found the following info and like it well better:

“Ctrl+s Ctrl+w”. This will search the current word, but you must move your cursor to the beginning of the word first.

http://xah-forum.blogspot.com/2009/08/search-word-under-cursor-in-emacs.html