I have an application that takes all the parameters in the url like this: /category/subcategory/sub-subcategory
. I want to be able to give out extra parameters
You can use alphanumeric, plus the special characters "$-_.+!*'()," More info here: http://www.ietf.org/rfc/rfc1738.txt
Also, take note not to exceed 2000 characters in url
The most recent URI spec is RFC 3986; see the ABNF for details on what characters are allowed in which parts for the URI.
The format for an absolute path part is:
path-absolute = "/" [ segment-nz *( "/" segment ) ]
segment = *pchar
segment-nz = 1*pchar
pchar = unreserved / pct-encoded / sub-delims / ":" / "@"
pct-encoded = "%" HEXDIG HEXDIG
unreserved = ALPHA / DIGIT / "-" / "." / "_" / "~"
sub-delims = "!" / "$" / "&" / "'" / "(" / ")"
/ "*" / "+" / "," / ";" / "="
You could use a dash or an underscore (these are used frequently). You could use any character you want to but for example, spaces turn into %20 in the url so they don't look too-nice.
See http://www.ietf.org/rfc/rfc1738.txt
Basically, you are allowed all aphanumerics as well as $ - _ . + ! * ' ( ) ,