Php > Miscellaneous

PHP Date Validation (including leap year)

PHP Date Validation (including leap year)

<? 

  function GetValidDate($month=1, $day=1, $year=1970) 
  { 
//** provide a default value and convert the day of the month given. Day 
//** cannot be less than 1 or greater than 31. 

    $day = min(31, max(1, intval($day))); 

//** provide a default value and convert the month number given. Month cannot 
//** be less than 1 or greater than 12. 

    $month = min(12, max(1, intval($month))); 

//** provide a default value and convert the day of the year number given. 

    $year = max(1970, intval($year)); 

//** handle compensating for day runover if the number of days selected is 
//** greater than those allowable for the selected month. 

    switch($month) 
    { 
//** if FEBRUARY the selected day must be corrected and a leap year must be 
//** acounted for as well. 
//** CHANGED JAN 26/2004 - corrected for leap year error. 

      case 2 : 
        if($day > 28) 
          $day = ($year % 4 == 0 && ($year % 100 != 0 || $year % 400 == 0)) ? 29 : 28; 
        break; 

//** only maximum of thirty days in these months. 

      case 4  :  //** APRIL 
      case 6  :  //** JUNE 
      case 9  :  //** SEPTEMBER 
      case 11 :  //** NOVEMBER 

        $day = min(30, $day); 
        break; 
    } 
//** construct the appropriate date timestamp from the parameters provided. 

    return mktime(0, 0, 0, $month, $day, $year); 
  } 
?> 

<html> 
<body> 
<form method="post"> 
  <font face="verdana"  size="2"> 

  <i>Please choose a date:</i><br> 
   
  <select name="month"> 
    <option value="1">January</option> 
    <option value="2">February</option> 
    <option value="3">March</option> 
    <option value="4">April</option> 
    <option value="5">May</option> 
    <option value="6">June</option> 
    <option value="7">July</option> 
    <option value="8">August</option> 
    <option value="9">September</option> 
    <option value="10">October</option> 
    <option value="11">November</option> 
    <option value="12">December</option> 
  </select> 

  <!-- generate a list of available days in a month, 1 to 31 --> 

  <select name="day"> 
    <? 
      for($index=1; $index <= 31; $index++) 
        echo "<option value='$index'>$index</option>"; 
    ?> 
  </select> 

  <!-- generate a list of years to select --> 

  <select name="year"> 
    <? 
      for($index=2000; $index <= 2025; $index++) 
        echo "<option value='$index'>$index</option>"; 
    ?> 
  </select> 

  <input type="submit" name="dodisplay" Value=" Validate "><br><br> 

  <!-- if this form was submitted display the date choosen. --> 
  <? 
    if(isset($_REQUEST["dodisplay"])) 
    { 
      echo "<i>You Choose:</i> <font color='blue'>", 
           date("F d, Y", GetValidDate($_REQUEST["month"],$_REQUEST["day"],$_REQUEST["year"])), 
           "</font> <i>(", "month=", $_REQUEST["month"], " day=", $_REQUEST["day"], 
           " year=", $_REQUEST["year"], ")</i>"; 
    } 
  ?> 
  </font> 

</form> 
</body> 
</html>