Bool isvalidemail (String Strin)
{
// Return True if Strin is in Valid E-mail format.
Return Regex.ismatch (Strin, @ "^ ([/ w - /.] ) @ (/ [[0-9] {1,3} /. [0-9] {1,3} /. 0-9] {1,3} /.) | ([/ W -] /.) )) ([A-ZA-Z] {2, 4} | [0-9] {1,3 }) (/]?) $ ");
}
