C# – Extract Email Addresses from Text File

Output Input.txt This text file contains eddiejackson1@test.com AA aa BB bb. This text file contains eddiejackson2@test.com CC cc DD dd. This text file contains eddiejackson3@test.com EE ee FF ff. This text file contains eddiejackson4@test.com 1234567890. This text file contains eddiejackson5@test.com 1234567890. This text file contains eddiejackson6@test.com 1234567890. Output.txt eddiejackson1@test.com eddiejackson2@test.com eddiejackson3@test.com eddiejackson4@test.com eddiejackson5@test.com eddiejackson6@test.com