Actually, technically it is possible, although it rather flies in the face of the store-and-forward model for email.
1) Parse the address 2) Look up the email domain, and find the MX server (mail server). 3) Contact the mail server on the incoming SMTP port, and be prepared to speak SMTP to it. 4) 'HELO <your domain name here>' -- this may be subject to various verification steps to prevent spamming. 4a) A response code of 250 indicates you're OK so far 5) RECV <email address here> 6) A response code in the 200's indicates success. A response in the 400's indicates a temporary failure, and in the 500's indicates that address isn't going to work. 7) Terminate the conversation at this point, rather than proceeding on with the protocol. That said, you don't want to do this. For one thing, all it verifies is that there is a mail server which will accept the mail. It doesn't mean it's the right address, or that it doesn't end up in a junk box somewhere. Servers are free to accept all mail, and discard unknown address instead of delivering it, and it's not a bad way to protect privacy. Also, you will have to contend with all the other countermeasures that SMTP servers implement to prevent spammers from using their system to deliver their junk. And finally -- even if you have a valid email address, you don't know if it is actually owned by the person entering it. That's why nobody does this. Instead, they ask for the email address twice, to catch typos, and then they send a verification email, with a verification link you click, to verify that you actually were able to receive it. This is a much stronger test, and more reliable, even if it is not as immediate in terms of user feedback. On Dec 9, 10:03 am, Mark Murphy <mmur...@commonsware.com> wrote: > 1. This is not related to Android. > > 2. It is not possible, short of sending the user an email and seeing > if it works. > > There are plenty of Java regular expressions you can use with the > Pattern and Matcher classes to make sure the email address is not > completely rubbish (e.g., missing the @ sign). > > On Thu, Dec 9, 2010 at 7:38 AM, Abhilash baddam > > > > > > > > > > <abhilash.androiddevelo...@gmail.com> wrote: > > Hi, > > iam new android..can any one tell how to do email validation in > > android... > > actually i have one edit text where the user have to enter email id.. > > how can i validate whether the user entered proper mail id or not. > > > Regards, > > Abhilash.B > > > -- > > You received this message because you are subscribed to the Google > > Groups "Android Developers" group. > > To post to this group, send email to android-developers@googlegroups.com > > To unsubscribe from this group, send email to > > android-developers+unsubscr...@googlegroups.com > > For more options, visit this group at > >http://groups.google.com/group/android-developers?hl=en > > -- > Mark Murphy (a Commons > Guy)http://commonsware.com|http://github.com/commonsguyhttp://commonsware.com/blog|http://twitter.com/commonsguy > > _The Busy Coder's Guide to *Advanced* Android Development_ Version 1.9 > Available! -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
