. Four cases of application of regular expression in net

1. Confirm valid e-mail format

The following code example uses the static Regex.IsMatch method to verify whether a string is a valid e-mail format. If the string contains a valid e-mail address, the IsValidEmail method returns True, otherwise it returns false without taking any other action. You can use IsValidEmail to filter e-mail addresses that contain invalid characters before an application stores the address in a database or displays it in a asp.net page.

Visual Basic code example

Function IsValidEmail (Strin as String) as Boolean

' Return True if

Strin are 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}) (]?) $")

End Function

C # code example

BOOL IsValidEmail (String strin)

{

Return true if Strin are 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}) (]?)

$");

}