Here is a regular expression for matching phone numbers - 10 digit phone numbers. An explanation can be found here http://www.websina.com/bugzero/kb/regexp.html at bottom of the page.

re = /\(?\d{3}\)?([-\/\.])\d{3}\1\d{4}/;

This is a little more robust than previous expression in that parentheses and separators are optional and can be "-", "/" or "."

function validatePhoneNumber(phoneElement){

if (isEmpty(phoneElement)){
return false;
}

var regex = /^((\+?1-)?\d\d\d-)?\d\d\d-\d\d\d\d$/;
console.log("phone=" + phoneElement.value);

if (phoneElement.value.match(regex)){
return true;
}
return false;
}

Can you write up a similar function to validate the US Zip codes by State?

If I have a drop-down containing all the states and then a text box for entering Zip, then my zip code should be validated according to the State selected above.

I tried using an Ajax callback to a Page Method and then checking the zip codes with State in the database, but its turning out to be too complicated.

Anand

var stripped = ph.replace(/[\s()+-]|ext\.?/gi, "");

// 10 is the minimum number of numbers required
return ((/\d{10,}/i).test(stripped));
}

Literal regexes are surrounded by slash (/) characters, like quotes surround string literals. The syntax is /[regex]/[flags].

So, the first regex is [\s()+-]|ext\.? which means: match either a whitespace, parenthesis, +, - OR the literal ext, optionally ending in a full-stop (period). When used with the replace function it removes the allowed characters from the string, leaving you with only numbers (if it's valid).

The next regex is \d{10,} which means match a string that consists of at least 10 digits, more is allowed. If there are less digits, it won't match. If alpha chars are present, it won't match. The number 10 is your minimum number of digits.

Note that in your solution the number 200txxxex200xxx200xxt.x2 is valid.

http://www.regular-expressions.info/ is a great regex resource, and the Mozilla JavaScript reference can be helpful too (http://developer.mozilla.org/en/docs/Core_JavaScript_1.5_Reference).

I hope this helps!

This should be more performant, maintainable and readable than the current solution. Note I haven't tested the above regexes, but they'd be close to the mark.