Regular expression problem

Hi all,

I am trying to create a regular expression that will allow
lower/upper letter, numbers, - , _ and ' (apostrophe) and spaces

This is what I have: /^[a-zA-Z0-9-_]+$/

when I try to add ' to it I get javascript error. the above doesn't work too It gives me a failed condition even when I only have letters and spaces in the field.

Thanks

a-z, A-Z, 0-9 and underscore are covered by \w. Your current regexp doesn't have a space in it, which explains the fail condition in your last comment. Try:

Depending on how you declare the regexp in JavaScript, you may have to escape the apostrophe (single quote) with a backslash before it.

This is my function:

function validateName(fld,nam){
var error = "";
var illegalChars = /^[\w' -]+$/;

if (fld.value == "") {
fld.style.background = 'Yellow';
error = "You didn't enter a "+ nam +".\n";
} else if (fld.value.length > 50) {
fld.style.background = 'Yellow';
error = ""+ nam +" is too long.\n";
} else if (illegalChars.test(fld.value)) {
fld.style.background = 'Yellow';
error = "Only letters, Numbers, - _ are allowed in "+ nam +"\n";
} else {
fld.style.background = 'White';
}

return error;
}

These are the values I have in the field:

firstname: Drew
lastname: Baskets

And it shows the error msg after testing the regexpression. I am not sure why it fails!!

That regular expression will match only valid strings. It looks like you're giving the error message whenever it does match, so it's backwards.