ROT13 (thing)

Update 2/26/02: DelFick /msg'ed me with his version that works for IE and Mozilla (confirmed). Cross browser capability automatically makes it better than mine and daglo's. Here's an easy-to-copy-&-paste version:

javascript: if(document.all)sel=document.selection.createRange().text; else{sel=getSelection().toString(); }if(!sel)sel=prompt('Enter the text to ROT13',''); alpha="abcdefghijklmnopqrstuvwxyz"; alpha+=alpha+alpha.toUpperCase()+alpha.toUpperCase(); for(i=0,result=""; i<sel.length; result+=(alpha.indexOf(sel.charAt(i))<0)? sel.charAt(i++): alpha.charAt(alpha.indexOf(sel.charAt(i++))+13)); void(alert(result));

The code looks like this:

javascript:
if(document.all)
  sel=document.selection.createRange().text;
else {
  sel=getSelection().toString();
}
if(!sel)sel=prompt('Enter the text to ROT13','');
alpha="abcdefghijklmnopqrstuvwxyz";
alpha+=alpha+alpha.toUpperCase()+alpha.toUpperCase();
for(i=0,result=""; i < sel.length;
  result+=(alpha.indexOf(sel.charAt(i)) < 0)?
  sel.charAt(i++):
  alpha.charAt(alpha.indexOf(sel.charAt(i++))+13)
);
void(alert(result));

Changing the last line to void(prompt('result:', result)); makes the bookmarklet into a rot-13 writer also, where you can easily copy the rot-13 encoded text.

---

Here is my version of a Mozilla rot-13 decoder bookmarklet in one line for easy copy-and-pasting:

javascript:p=document.getSelection();if(!p)p=prompt('Text:',''); q=''; for(i=0;i<p.length;i++) {c=p.charCodeAt(i); q+=String.fromCharCode (c+((c<65)^(c<91)^(c<97)^(c<123)? (c-1)%32<13? 13:-13:0))}alert(q)

Paste this as the location of a bookmark, and you've got a rot13 decoding button. For the curious, an easier-to-read version of the same thing:

javascript:
p=document.getSelection();
if(!p)p=prompt('Text...','');
q='';
for(i=0; i<p.length; i++){
  c=p.charCodeAt(i);
  q+=String.fromCharCode(
    c+((c<65)^(c<91)^(c<97)^(c<123)? // *1
    (c-1)%32<13?13:-13:0)            // *2
  );
}
alert(q)

// *1 - true iff c represents an alphabet
// *2 - decide btwn move forward and loop around

Added functionality: works on selected text, a la Netscape Everything Search Button-style. Select a rot13 encoded text, and press the decoder button. If nothing is selected, a dialog box pops up asking you for text.

Test it here!

Guvf znl abg pbzr va unaql...