如何修复未定义的索引警告？

Question

这是我得到的警告。

未定义索引：第8行/var/www/html/ies.aacrao.org/apply/begin.php中的errormsg

在这行代码上：

if ($_GET['errormsg'] == "no_appid") {

$_SESSION['errormsg'] = "There was a problem with your application.  Please reenter all data.";

}

希望有人能帮助我。

Answer 1

表示未设置$_GET['errormsg']。你可以这样检查：

if (isset($_GET['errormsg']) && $_GET['errormsg'] == "no_appid") {
}

Answer 2

您可以与isset一样查看

if (isset($_GET['errormsg']) && $_GET['errormsg'] == 'no_appid') {
    $_SESSION['errormsg'] = "There was a problem with your application.  Please reenter all data.";
}

查看php isset