make a session user have a automatic code input

when a user logs i开发者_开发百科n, I want a input type text to be already filled with some pre-determined letter...

how can I make that possible?

You can do it in two ways:-

1. You can give control from the Admin area, so that the Administrator has the full control. This can be possible by providing a list drop down with all the recommended alphabets, in the Settings section of your Admin area, and let the Admin choose her preferred alphabet & store it in the database. Then you can retrieve it from the database & show it in the front-end when any user logs in.

2. When the user logs in, you can generate a random letter, using the PHP function "rand()".

One simple code snippet for the second solution will be:-

<?php
// This function considers both the cases for each of the letters.
function randLetter() {
    $int = rand(0, 51);
    $a_z = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
    $rand_letter = $a_z[$int];
    return $rand_letter;
}


/**
 * This function considers only one specific cases for each of the letters.
 */
function randSpecificCaseLetter($lower_case = TRUE) {
    if ($lower_case) {
        $letter = chr(rand(97, 122));
    }
    else {
        $letter = chr(rand(65, 90));
    }

    return $letter;
}
?>

Hope it helps.