Upper case / Lower case functions

By davidjmedlock

…posted by davidjmedlock:

This originated out of some project I was thinking about doing and I though it’d be useful for others. These functions check to see if a character is upper case or lower case:

function isUpperCase(character) {
if (Asc(character) gte 65 and Asc(character) lte 90) {
return true;
else {
return false;

function isLowerCase(character) {
if (Asc(character) gte 97 and Asc(character) lte 122) {
return true;
else {
return false;


Have fun with it.

  • http://www.delyrical.com davidjmedlock

    Forgot to add this:

    if (Len(character) gt 1)
    return false;

    to the top of each of those functions. That way if they pass in a string, it won’t bomb. (It shouldn’t anyway. It should just return whether the first character is upper or lowercase…)

  • Tony Brandner

    Nice – we might actually use that one. We love CF functions.

    Be sure to add it to cflib.org!


  • Nathan Strutz

    What about a whole string? Here’s my function:

    function stringIsUppercase(str) {
    if(reFind(“^[A-Z]+$”,arguments.str)) return true;
    else return false;



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