undefined-index

问题 I'm running a PHP script and continue to receive errors like: Notice: Undefined variable: my_variable_name in C:\wamp\www\mypath\index.php on line 10 Notice: Undefined index: my_index C:\wamp\www\mypath\index.php on line 11 Line 10 and 11 looks like this: echo "My variable value is: " . $my_variable_name; echo "My index value is: " . $my_array["my_index"]; What is the meaning of these error messages? Why do they appear all of a sudden? I used to use this script for years and I've never had

问题 I'm receiving the error below when using phpMyAdmin. It's occurring every time I create any table. Notice in ./libraries/structure.lib.php#1881 Undefined index: Rows Backtrace ./libraries/structure.lib.php#2382: getHtmlForRowStatsTable( array, NULL, boolean false, boolean false, string '', string '', ) ./libraries/display_structure.inc.php#263: PMA_getHtmlForDisplayTableStats( string '', NULL, NULL, boolean false, NULL, string '?db=btc_orders&table=Rep&token=09aa3ad5cb85e33dad2a2098ed2874e2

问题 When I try to access an array by key which is not exists in this array, php will raise "undefined index" notice error. When I try to do the same on strings, "Illegal string offset " warning is raised. This is an expected behavior and I know how to deal with it. But when I tried this on boolean or integer values nothing happens: ini_set('display_errors', 1); error_reporting(E_ALL); $var = false; var_dump($var['test']); I expect to see some error messages, but $var['test'] just silently sets to

问题 This question already has answers here : “Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP (28 answers) Closed 3 years ago . I am trying to relearn some PHP basics for making a simple login script, however I get an error I have not received before(I made the same script a little over a year ago and never had this error. I simplified the code as much as I could to test to see which area was problematic and here is the issue: <?php $user = $_POST[

问题 I\'m running a PHP script and continue to receive errors like: Notice: Undefined variable: my_variable_name in C:\\wamp\\www\\mypath\\index.php on line 10 Notice: Undefined index: my_index C:\\wamp\\www\\mypath\\index.php on line 11 Line 10 and 11 looks like this: echo \"My variable value is: \" . $my_variable_name; echo \"My index value is: \" . $my_array[\"my_index\"]; What is the meaning of these error messages? Why do they appear all of a sudden? I used to use this script for years and I\