you can use
function to separate the comma separated email address.
If you use
thn in the output you will get an array of those email addresses.the code ll be as follows:
string strEmailaddress = Textbox.text;
string  EmailArr = strEmailAddress.split(',');
Now if there is multiple value then the array will be
Now you can take single element from this array by
and can insert into DB.
Hope this will help you.