how to make a function that validates fields in a form? php [closed]

by

Here is a simple implementation –

function validateUserName($uname){
  $illegalCharacters = array('!','@','#');

  // first check the length
  $length = strlen($uname);
  if ($length < 5 && $length > 10){
    return false;
  }else{
    // now check for illegal characters
    foreach($illegalCharacters AS $char){
      if (strpos($uname,$char) != -1){
        return false;
      }
    }
  }
  return true;
}

$userName = "user1905577";
if (validateUserName($username)){
  echo "Valid username!";
}else{
  echo "INVALID username!";
}

Lets see what is going on here –

We first use strlen() to test the length of the username and then iterate over all the illegal characters we defined and use strpos() to see if any appear in the username.

The function’s name is validateUserName and we can call it by simply placing it’s name and brackets afterwards. Like this – validateUserName(). This function has to receive a parameter (the username), so we pass that within the brackets, Like this – validateUserName($username)

More Related Contents:

  1. What does this function returns exactly? [closed]
  2. PHP function to generate v4 UUID
  3. Laravel 5.2 Validation Error not appearing in blade
  4. PHP echo vs PHP short echo tags
  5. Easy way to test a URL for 404 in PHP?
  6. What is the difference between PHP echo and PHP return in plain English?
  7. PHP variables in anonymous functions
  8. Passing an Array as Arguments, not an Array, in PHP
  9. Round up to nearest multiple of five in PHP
  10. PHP append one array to another (not array_push or +)
  11. Autoloader for functions
  12. PHP function use variable from outside
  13. Equivalent of include() in HTML
  14. Any way to specify optional parameter values in PHP?
  15. Delete digits after two decimal points, without rounding the value
  16. How do I remove the URL protocol and slash from user input in PHP
  17. Validating Crontab Entries with PHP
  18. Multiple excerpt lengths in wordpress
  19. Dynamic static method call in PHP?
  20. RGB to closest predefined color
  21. Timeout a function in PHP
  22. How to alias a function in PHP?
  23. required_if Laravel 5 validation
  24. Modify an Existing PHP Function to Return a String
  25. How do I get the function name inside a function in PHP?
  26. PHP pass function name as param then call the function?
  27. Number in the top-level domain?
  28. Changing a global variable from inside a function PHP
  29. Use Variable as Function Name in PHP [duplicate]
  30. Validate date format in php

Leave a Comment