A Self-Processing Get Form

This PHP example program demonstrates how to write and handle a self-processing get form.

SelfProcessingGet.php

<!DOCTYPE html>
<html>
<head>
  <title>XoaX.net's PHP</title>
</head>
<body>
<?php
  $dInches = NULL;
  if (isset($_GET['sInches'])) {
    $dInches = $_GET['sInches'];
  }
  // The initial request
  if (!is_numeric($dInches)) {
?>

<form action="<?php echo $_SERVER['PHP_SELF'] ?>" method="GET">
  Inches: <input type="text" name="sInches" /><br /><br />
  <input type="submit" name"sConvert">
</form>

<?php
  // The subsequent request
  } else {
    $dCentimeters = (2.54*$dInches);
    printf("%g inches = %g centimeters", $dInches, $dCentimeters);
  }
?>

</body>
</html>

Core PHP

A Self-Processing Get Form

SelfProcessingGet.php

Output