I need a regular expression that would limit the number of characters to 100 and allow the use of 0-9 ,! @.,;: '"? - and all lower and upper case letters
/^[0-9A-Za-z!@.,;:'"?-]{1,100}\z/
Language dependent but should be
^[0-9A-Za-z!@\.;:'"?-]{1,100}$
As stated in the comments, and just to avoid using bad examples:
^[0-9A-Za-z!@.,;:'"?-]{1,100}\z
^(.{1,100})$
. {1,100} , , , min max count
.
{1,100}