Caesars Cipher Algorithm (Javascript)

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Caesar cipher script
var mode = "ceaser";
var shift;
function encrypt(text, shift) {
	var result = "";
	if (mode == "ceaser"){

		//loop through each caharacter in the text
		for (var i = 0; i < text.length; i++) {
             
             //get the character code of each letter
            var c = text.charCodeAt(i);

            // handle uppercase letters
			if(c >= 65 && c <=  90) {
		       result += String.fromCharCode((c - 65 + shift) % 26 + 65); 

            // handle lowercase letters
	        }else if(c >= 97 && c <= 122){
	        	result += String.fromCharCode((c - 97 + shift) % 26 + 97);

            // its not a letter, let it through
	        }else {
	        	result += text.charAt(i);
	        }
		}
	}
	return result;
}

function decrypt(text,shift){
	var result = "";
	shift = (26 - shift) % 26;
	result = encrypt(text,shift);
	return result;
}	
How it works
Posted in Javascript, Programming and tagged .