Yes @wyrfel is right, you use wp_insert_post() to create your posts. Using your 50 US States example I’ve created some code you can drop into your theme’s functions.php to see how it works (although you’ll probably not want to call add_states_if_not_yet_added() for every page load, but the example is easier to show it this way):
<?php
add_action('init','init_us_states');
function init_us_states() {
register_us_states_post_type();
add_states_if_not_yet_added();
}
function add_states_if_not_yet_added() {
foreach(get_50_us_states() as $state_code => $state_name) {
if (!get_page_by_path($state_code,OBJECT,'us-state'))
wp_insert_post(array(
'post_type' => "us-state",
'post_content' => "Information about {$state_name}",
'post_title' => $state_name, // i.e. 'Georgia'
'post_name' => $state_code, // i.e. 'GA'; this is for the URL
'post_status' => "publish",
'comment_status' => "closed",
'ping_status' => "closed",
'post_parent' => "0",
));
}
}
function register_us_states_post_type() {
register_post_type('us-state',array(
'labels' => array(
'name' => _x('States', 'post type general name'),
'singular_name' => _x('State', 'post type singular name'),
'add_new' => _x('Add New', 'us-state'),
'add_new_item' => __('Add New State'),
'edit_item' => __('Edit State'),
'new_item' => __('New State'),
'view_item' => __('View State'),
'search_items' => __('Search States'),
'not_found' => __('No States found'),
'not_found_in_trash' => __('No States found in Trash'),
'parent_item_colon' => '',
'menu_name' => 'States'
),
'public' => true,
'publicly_queryable' => true,
'show_ui' => true,
'show_in_menu' => true,
'query_var' => true,
'rewrite' => array('slug'=>'states'),
'capability_type' => 'post',
'has_archive' => 'states',
'hierarchical' => false,
'supports' => array('title','editor','author','thumbnail','excerpt')
));
}
function get_50_us_states() {
return array(
'AL' => 'Alabama',
'AK' => 'Alaska',
'AZ' => 'Arizona',
'AR' => 'Arkansas',
'CA' => 'California',
'CO' => 'Colorado',
'CT' => 'Connecticut',
'DE' => 'Delaware',
'FL' => 'Florida',
'GA' => 'Georgia',
'HI' => 'Hawaii',
'ID' => 'Idaho',
'IL' => 'Illinois',
'IN' => 'Indiana',
'IA' => 'Iowa',
'KS' => 'Kansas',
'KY' => 'Kentucky',
'LA' => 'Louisiana',
'ME' => 'Maine',
'MD' => 'Maryland',
'MA' => 'Massachusetts',
'MI' => 'Michigan',
'MN' => 'Minnesota',
'MS' => 'Mississippi',
'MO' => 'Missouri',
'MT' => 'Montana',
'NE' => 'Nebraska',
'NV' => 'Nevada',
'NH' => 'New Hampshire',
'NJ' => 'New Jersey',
'NM' => 'New Mexico',
'NY' => 'New York',
'NC' => 'North Carolina',
'ND' => 'North Dakota',
'OH' => 'Ohio',
'OK' => 'Oklahoma',
'OR' => 'Oregon',
'PA' => 'Pennsylvania',
'RI' => 'Rhode Island',
'SC' => 'South Carolina',
'SD' => 'South Dakota',
'TN' => 'Tennessee',
'TX' => 'Texas',
'UT' => 'Utah',
'VT' => 'Vermont',
'VA' => 'Virginia',
'WA' => 'Washington',
'WV' => 'West Virginia',
'WI' => 'Wisconsin',
'WY' => 'Wyoming',
);
}
And here’s some screenshots showing it in use:
