Listing 27.4 get_accounts Function from mail_fns.php—Function to Retrieve All the Account Details for a Particular User function get_accounts$auth_user { $list = array; ifdb_connect { $q
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existing record.This function is in the output_fns.php library; it simply outputs HTML
so we will not go through it here.
The function that retrieves any existing accounts is get_accounts(), from the mail_fns.phplibrary.This function is shown in Listing 27.4.
Listing 27.4 get_accounts() Function from mail_fns.php—Function to Retrieve All the
Account Details for a Particular User
function get_accounts($auth_user) {
$list = array();
if(db_connect()) {
$query = "select * from accounts where username = '$auth_user'";
$result = mysql_query($query);
if($result) {
while($settings = mysql_fetch_array($result)) array_push( $list, $settings);
} else return false;
} return $list;
}
As you can see, this function connects to the database, retrieves all the accounts for a particular user, and returns them as an array.
Creating a New Account
If a user fills out the account form and clicks the Save Changes button, the store-set-tingsaction will be activated Let’s look at the event handling code for this from index.php In the preprocessing stage, we execute the following code:
case 'store-settings' : {
store_account_settings($HTTP_SESSION_VARS['auth_user'], $HTTP_POST_VARS); break;
}
The store_account_settings()function writes the new account details into the data-base.The code for this function is shown in Listing 27.5.
Listing 27.5 store_account_settings() Function from mail_fns.php—Function to Save
New Account Details for a User
function store_account_settings($auth_user, $settings) {
Trang 2{ echo 'All fields must be filled in Try again.<br /><br />';
return false;
} else { if($settings['account']>0)
$query = "update accounts set server = '$settings[server]',
port = $settings[port], type = '$settings[type]', remoteuser = '$settings[remoteuser]',
remotepassword = '$settings[remotepassword]' where accountid = $settings[account]
and username = '$auth_user'";
else
$query = "insert into accounts values ('$auth_user',
'$settings[server]', $settings[port], '$settings[type]', '$settings[remoteuser]', '$settings[remotepassword]', NULL)";
if(db_connect() && mysql_query($query)) {
return true;
} else { echo 'could not store changes.<br /><br /><br /><br /><br /><br />';
return false;
} } }
As you can see, two choices within this function correspond to inserting a new account
or updating an existing account.The function executes the appropriate query to save the account details.
After storing the account details, we go back to index.php, to the main body stage:
case 'store-settings' : case 'account-setup' : case 'delete-account' : {
display_account_setup($HTTP_SESSION_VARS['auth_user']);
break;
}
As you can see, we then execute the display_account_setup() function as before to list the user’s account details.The newly added account will now be included.
Listing 27.5 Continued
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Modifying an Existing Account
The process for modifying an existing account is very similar.The user can change the account details and click the Save Changes button Again this will trigger the
store-settingsaction, but this time it will update the account details instead of insert-ing them.
Deleting an Account
To delete an account, the user can click the Delete Account button that is shown under each account listing.This activates the delete-accountaction.
In the preprocessing section of the index.phpscript, we will execute the following code:
case 'delete-account' : {
delete_account($HTTP_SESSION_VARS['auth_user'], $account);
break;
}
This code calls the delete_account()function.The code for this function is shown in Listing 27.6 Deleting accounts needs to be handled before the header because a choice
of which account to use is inside the header.The account list needs to be updated before this can be correctly drawn.
Listing 27.6 delete_account() Function from mail_fns.php—Function to Delete a
Single Account’s Details
function delete_account($auth_user, $accountid) {
//delete one of this user's account from the DB
$query = "delete from accounts where accountid='$accountid'
and username ='$auth_user'";
if(db_connect()) {
$result = mysql_query($query);
} return $result;
}
After execution returns toindex.php, the body stage will run the following code: case 'store-settings' :
case 'account-setup' : case 'delete-account' : {
display_account_setup($HTTP_SESSION_VARS['auth_user']);
break;
Trang 4You will recognize this as the same code we ran before—it just displays the list of the user’s accounts.
Reading Mail
After the user has set up some accounts, we can move on to the main game: connecting
to these accounts and reading mail.
Selecting an Account
We need to select one of the user’s accounts to read mail from.The currently selected account is stored in the $selected_accountsession variable.
If the user has a single account registered in the system, it will be automatically selected when he logs in, as follows:
if(number_of_accounts($HTTP_SESSION_VARS['auth_user'])==1) {
$accounts = get_account_list($HTTP_SESSION_VARS['auth_user']);
$HTTP_SESSION_VARS['selected_account'] = $accounts[0];
}
Thenumber_of_accounts()function, from mail_fns.php, is used to work out whether the user has more than one account.The get_account_list()function retrieves an array of the names of the user’s accounts In this case there is exactly one, so we can access it as the array’s 0value.
The number_of_accounts()function is shown in Listing 27.7.
Listing 27.7 number_of_accounts() Function from mail_fns.php—Function to Work
Out How Many Accounts a User Has Registered
function number_of_accounts($auth_user) {
// get the number of accounts that belong to this user
$query = "select count(*) from accounts where username = '$auth_user'";
if(db_connect()) {
$result = mysql_query($query);
if($result) return mysql_result($result, 0, 0);
} return 0;
}
The get_account_list()function is similar to the get_accounts()function we looked at before except that it only retrieves the account names.
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If a user has multiple accounts registered, he will need to select one to use In this case, the headers will contain a SELECTthat lists the available mailboxes Choosing the appro-priate one will automatically display the mailbox for that account.You can see this in Figure 27.5.
Figure 27.5 After the localhost account is selected from the SELECTbox,
the mail from that account is downloaded and displayed
This SELECToption is generated in the do_html_header()function from output_fns.php, as shown in the following code fragment:
// include the account select box only if the user has more than one account if(number_of_accounts($auth_user)>1)
{ echo '<form target="index.php?action=open-mailbox" method="post">';
echo '<td bgcolor="#ff6600" align="right" valign="middle">';
display_account_select($auth_user, $selected_account);
echo '</td>';
echo '</form>';
}
We have generally avoided discussing the HTML used in the examples in this book, but the HTML generated by the function display_account_select()bears a visit Depending on the accounts the current user has,display_account_select()will generate HTML like this: