I need to split an email address and take out the first character and the first character after the '@'
I can do this as follows:
'bar@foo'.split('@').map(function(a){ return a.charAt(0); }).join('')
--> bf
Now I was wondering if it can be done using a regex match, something like this
'bar@foo'.match(/^(\w).*?@(\w)/).join('')
--> bar@fbf
Not really what I want, but I'm sure I miss something here! Any suggestions ?
Why use a regex for this? just use indexOf to get the char at any given position:
var addr = 'foo@bar';
console.log(addr[0], addr[addr.indexOf('@')+1])
To ensure your code works on all browsers, you might want to use charAt instead of []:
console.log(addr.charAt(0), addr.charAt(addr.indexOf('@')+1));
Either way, It'll work just fine, and This is undeniably the fastest approach
If you are going to persist, and choose a regex, then you should realize that the match method returns an array containing 3 strings, in your case:
/^(\w).*?@(\w)/
["the whole match",//start of string + first char + .*?@ + first string after @
"groupw 1 \w",//first char
"group 2 \w"//first char after @
]
So addr.match(/^(\w).*?@(\w)/).slice(1).join('') is probably what you want.
If I understand correctly, you are quite close. Just don't join everything returned by match because the first element is the entire matched string.
'bar@foo'.match(/^(\w).*?@(\w)/).splice(1).join('')
--> bf
Using regex:
matched="",
'abc@xyz'.replace(/(?:^|@)(\w)/g, function($0, $1) { matched += $1; return $0; });
console.log(matched);
// ax
The regex match function returns an array of all matches, where the first one is the 'full text' of the match, followed by every sub-group. In your case, it returns this:
bar@f
b
f
To get rid of the first item (the full match), use slice:
'bar@foo'.match(/^(\w).*?@(\w)/).slice(1).join('\r')
Use String.prototype.replace with regular expression:
'bar@foo'.replace(/^(\w).*@(\w).*$/, '$1$2'); // "bf"
Or using RegEx
^([a-zA-Z0-9])[a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@([a-zA-Z0-9-])[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$
s[p]lice the result array before calling join