Macro: ROT13 – simple letter substitution caesar cipher

The other day i wanted to know what is written in the registry under ‘UserAssist’.
I know i can decrypt them by using an additional entry ‘NoEncrypt’
but it was not my pc and i just wanted to know something quickly.

So i remembered i did this coding already twice in other languages and now i wanted to see
if i am skilled enough to do this in JavaScript again… and it worked.

Examples:
FROM:
{0139Q44R-6NSR-49S2-8690-3QNSPNR6SSO8}Zvpebfbsg BssvprZvpebfbsg Rkpry 2010.yax=””
TO:
{0139D44E-6AFE-49F2-8690-3DAFCAE6FFB8}Microsoft OfficeMicrosoft Excel 2010.lnk=””

FROM:
clipboardData.setData( sDataFormat, sData, iPos );
EmEditor ROT13 macro
TO:
pyvcobneqQngn.frgQngn( fQngnSbezng, fQngn, vCbf );
RzRqvgbe EBG13 znpeb

ROT13 is an very simple letter substitution cipher know too as caesar cipher.
http://en.wikipedia.org/wiki/ROT13

Here is my code:

	

	// INPUT =================================

	//Sel = clipboardData.getData("Text"); 

	Sel = document.selection.Text;

	if(Sel.length == 0)  quit();

	//Sel = Sel.replace(/(^s*)|(s*$)/g, ""); //LTrim/RTrim

	//if(Sel.length > 20000) Sel = Sel.substr(0, 20000); //not to many please ;-)

	out ="";

	

	// CODE =================================

	for(Pos=0,strLen=Sel.length;Pos<strLen;Pos++){

		nASC = Sel.charCodeAt(Pos);

	

		if(nASC > 64 && nASC < 91){

			nASC = nASC +13;

			if(nASC > 90){nASC -= 26;}

			out += String.fromCharCode(nASC);

		}else if(nASC > 96 && nASC < 123){

			nASC = nASC +13;

			if(nASC > 122){nASC -= 26;}

			out += String.fromCharCode(nASC);

		}else{ 

			out += Sel.charAt(Pos);

		}

	

	}

	// OUTPUT =================================

	// //Out to an dialog:

	// if(Sel.length > 1000) Sel = Sel.substr(0, 1000); //shorten for the dialog box

	// if(out.length > 1000) out = out.substr(0, 1000); //   remove for to insert into an document

	// alert(Sel + 'nn' + Sel.length + ' signs ROT13 =>nn' + out);

	

	// //Replace clipboard with processed text: 

	// clipboardData.setData("Text", out);

	

	//Replace selected text with processed text:

	document.selection.Text = out;

	

	

(why are this code blocks always that small in this forum? Or is this an firefox issue?)