email id validation in asp.net?

In my web application i have a textbox with multiline 开发者_JS百科property is true, when ever i type emailids separating with comma how can i validate multiple emailid in this situation.

like: sasidhar@yahoo.com,surya@gmail.com in a textbox how can i validate please help me

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Here's the general idea:

Split the values and store it into an array, then validate it using (I recommend this): http://www.coveryourasp.com/ShowSource.asp?page=ValidateEmail