case-insensitive regex for colon in a string

I am trying to match a string that has the form:

abcd:vxyz

That is: 4 chars followed by a colon then followed by three (or maximum) 4 chars.

I want to do case INSENSITIVE matches.

Can anyone help w开发者_StackOverflow中文版ith the pattern?

/^[a-z]{4}:[a-z]{3,4}$/i

........

The following regex should work:

"^[a-zA-Z]{4}:[a-zA-Z]{3,4}$"

The {4} part indicates that it should match exactly four copies of the previous symbol, which can be any character between 'a' and 'z', as well as 'A' and 'Z', inclusive.

The {3,4} part creates a range of copies between 3 and 4 inclusive, while the '^' symbol indicates that it should start at the beginning of the given string and the '$' sign indicates that it should end at the end of the given string.

Your example was alphabetical, but it was unclear if your desired regex should be limited to that. If you wanted to match any characters in those groups:

/^.{4}:.{3,4}$/i

Another non-regex way to do this would be to split() on the colon. Check for length 4 on the first element, and length 3 or 4 on the second element.

var foo = 'abcd:123a';
var bar = 'fds:0';

var af = foo.split(':');
var isMatch = ((af[0].length==4) && (af[1].length==3 || af[1].length==4));
alert (isMatch);

var ab = bar.split(':');
alert ((ab[0].length==4) && (ab[1].length==3 || ab[1].length==4));