Easily convert a state name to the state abbreviation.

state_name_to_abbreviation.php

<?php

function convert_state_to_abbreviation($state) {
  //If there is no text in the $state variable
  if($state == '') {
    //Exit this function
    return false;
  }
  
  //Array of state names & abbreviations
  $state_list = array(
    'Alabama'        => 'AL',
    'Alaska'         => 'AK',
    'Arizona'        => 'AZ',
    'Arkansas'       => 'AR',
    'California'     => 'CA',
    'Colorado'       => 'CO',
    'Connecticut'    => 'CT',
    'Delaware'       => 'DE',
    'Florida'        => 'FL',
    'Georgia'        => 'GA',
    'Hawaii'         => 'HI',
    'Idaho'          => 'ID',
    'Illinois'       => 'IL',
    'Indiana'        => 'IN',
    'Iowa'           => 'IA',
    'Kansas'         => 'KS',
    'Kentucky'       => 'KY',
    'Louisiana'      => 'LA',
    'Maine'          => 'ME',
    'Maryland'       => 'MD',
    'Massachusetts'  => 'MA',
    'Michigan'       => 'MI',
    'Minnesota'      => 'MN',
    'Mississippi'    => 'MS',
    'Missouri'       => 'MO',
    'Montana'        => 'MT',
    'Nebraska'       => 'NE',
    'Nevada'         => 'NV',
    'New Hampshire'  => 'NH',
    'New Jersey'     => 'NJ',
    'New Mexico'     => 'NM',
    'New York'       => 'NY',
    'North Carolina' => 'NC',
    'North Dakota'   => 'ND',
    'Ohio'           => 'OH',
    'Oklahoma'       => 'OK',
    'Oregon'         => 'OR',
    'Pennsylvania'   => 'PA',
    'Rhode Island'   => 'RI',
    'South Carolina' => 'SC',
    'South Dakota'   => 'SD',
    'Tennessee'      => 'TN',
    'Texas'          => 'TX',
    'Utah'           => 'UT',
    'Vermont'        => 'VT',
    'Virginia'       => 'VA',
    'Washington'     => 'WA',
    'West Virginia'  => 'WV',
    'Wisconsin'      => 'WI',
    'Wyoming'        => 'WY'
  );

  //Prepare the state name
  $state_name = trim($state);
  $state_name = ucwords($state_name);
  
  //If the state name is valid
  if (array_key_exists($state_name, $state_list)) {
    //Set the abbreviation
    $state_abbreviation = $state_list[$state_name];
    
    //Return the abbreviation
    return $state_abbreviation;
    
  } else {
    //Exit the function
    return false;
  }
}