Email Validation


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Email Validation

  1. 1. Hashim Naseer Lokasher Muazzam Ali Sundhu Haseeb Mehmood Gohar Naseer Muhammad Qasim Ali 11014119-129 11014119-099 11014119-089 11014119-087 11014119-128 THEORY OF AUTOMATA PROJECT TITLE: EMAIL VALIDATOR
  2. 2. Introduction Email Validator
  3. 3. Email Validator What does Validation means?
  4. 4. Validation Validation is the process of checking data against a standard or requirement. The term is commonly used when: Checking the information entered by a person when storing data, sending information or using an online service (FORM VALIDATION).
  5. 5. Email Validation So, Email Validation means to validate and check an email address.
  6. 6. Our Project Is a email validator, which Validates an Email Address Check the grammar and syntax Can be used in Data Entry forms and Applications
  7. 7. Screenshot C# Programming Language is used for the development of this application. WinForm and Regular Expressions class is also used
  8. 8. Program Working Email Validator
  9. 9. So, What is a Valid Email Address?
  10. 10. Valid Email Address There's only one real answer to this: A valid email address is one that you can send emails to Contemporary email addresses consist of a "local part" separated from a "domain part" (a fully-qualified domain name) by an at-sign ("@").  is a valid Email Address
  11. 11. Regular Expressions  If you only want to check if an address is grammatically correct then you could use a regular expression  Using a regular expression that recognizes email addresses could be useful in various situations: For example to scan for email addresses in a document, to validate user input, or as an integrity constraint on a data repository.
  12. 12. Regular Expressions Regular expressions are a very cool feature for pattern recognition in strings. Mathematically speaking regular expressions are parsed through a "finite state machine". As the name implies, such a machine has only a finite number of states, and it has no external memory attached.
  13. 13. Parsing Parsing or syntactic analysis is the process of analysing a string of symbols, either in natural language or in computer languages, according to the rules of a formal grammar.
  14. 14. Regular Expression Processor A regular expression processor processes a regular expression statement expressed in terms of a grammar in a given formal language, and with that examines the target text string, parsing it to identify substrings that are members of its language, the regular expressions.
  15. 15. "^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+.[a-zA-Z0-9-.]+$"
  16. 16. Regular Expression for Email Validation can be validated as "^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+.[a-zA-Z0-9-.]+$" Myname @ mycompany . com We compared the given email address with the upper RegEx to validate it is synthetically correct or not.
  17. 17. Regular Expressions Any validation problems that involve recursion, option, limitation is easier to solve with regular expressions than using other ways (like if-else if-else, while condition)
  18. 18. Regular Expressions Regular Expressions can be used to Test if a string matches some pattern. Scan for virus signatures. Process natural language. Search for information using Google. Search for markers in human genome Search-and-replace in a word processors. Validate data-entry fields (dates, email, URL, credit card)
  19. 19. Email Address Standards There are acknowledged standards for what constitutes a valid email address. These are defined in the Request For Comments documents (RFCs) The syntax of email addresses has been defined in various RFCs, most notably RFC 822 and RFC 5322. We u s e d R F C 5 3 2 2 , a s t h i s i s t h e l a t e s t s t a n d a r d .
  20. 20. Code Snippet string pattern = @"^[a-z][a-z|0-9|]*([_][a-z|0-9]+)*([.][a-z|" + @"0-9]+([_][a-z|0-9]+)*)?@[a-z][a-z|0-9|]*.([a-z]" + @"[a-z|0-9]*(.[a-z][a-z|0-9]*)?)$"; System.Text.RegularExpressions.Match match = Regex.Match(textBox1.Text.Trim(), pattern, RegexOptions.IgnoreCase);
  21. 21. Finite State Machine
  22. 22. ANY Question?
  23. 23. Thanks