explain the Concept behind in this??

[srinidelite]

var RE_SSN = /^[0-9]{3}[- ]?[0-9]{2}[- ]?[0-9]{4}$/;

hello ,

i would like to know what is the meaning behind in these ^ ,[- ],$ symbols???

and i would able to follow that the script logically verifying the format of text being entered!!

i.e NNN-NN-NNNN...

Thanks in Advance ..

Srini.

[DavidAntaramian]

You're looking at a regular expression. The pattern that is defined in this expression happens as follows:

• / opens the regular expression
• ^ specifies that the match must be at the start of the string being queried
• [0-9] match any numeric character
• {3} the previous statement should be matched exactly three times
• [- ] match the hyphen or space character
• ? there should be either zero or one of the preceeding match
• [0-9] match any numeric character
• {2} the previous statement should be matched exactly two times
• [- ] match the hyphen or space character
• ? there should be either zero or one of the preceeding match
• [0-9] match any numeric character
• {4} the previous statement should be matched exactly four times
• $ specifies that the string is only a match if it has now reached the end of the string

This expression when run will match the following strings, where n is any digit:

• nnn-nn-nnnn
• nnn-nn nnnn
• nnn nn-nnnn
• nnn nn nnnn
• nnnnn nnnn
• nnnnn-nnnn
• nnn-nnnnnn
• nnn nnnnnn
• nnnnnnnnn

It will not, however, match strings like the following:

• nnn*nn*nnn
• nn-nnn-nnnn

Does that make sense?

[srinidelite]

@DavidAntaramian .... Thanks for Reply .