php - 发生错误后不要清除文本框值

Question

我希望在发送数据后，如果发生错误，它不会删除已经写入文本框或复选框的数据。我怎样才能做到这一点？这是 html 代码:

<form action="adaugare-elev.php?actiune=validare" method="post">
    Date de contact <br>
    <table>
       <tr><td>Nume: <th><input type="text" name="nume" required></th></td></tr>
       <tr><td>Prenume: <th><input type="text" name="prenume" required></th></td></tr>
       <tr><td>Seria: <input type="text" style="width:25px;" name="seria" required></td> <td>Nr: <input type="text" name="nr" style="width:50px;" name="nr" required></td></tr>
       <tr><td>CNP: <th><input type="text" name="cnp" required></th></td></tr>
       <tr><td>Mail: <th><input type="text" name="mail" required></th></td></tr>
       <tr><td>Loc de munca: <th><input type="text" name="locmunca" required></th></td></tr>
    </table><br>
</form>

这是表单的 php 代码:

if(!isset($_GET['actiune'])) 
    $_GET['actiune'] = '';
switch($_GET['actiune'])
{
    case 'validare':
       $_SESSION['nume'] = $_POST['nume'];
       $_SESSION['prenume'] = $_POST['prenume'];
       $_SESSION['seria'] = $_POST['seria'];
       $_SESSION['nr'] = $_POST['nr'];
       $_SESSION['cnp'] = $_POST['cnp'];
       $_SESSION['mail'] = $_POST['mail'];
       $_SESSION['locmunca'] = $_POST['locmunca'];
       $inserare = "insert into `elevi` (`nume`,`prenume`,`nr`,`cnp`,`mail`,`locmunca`,) values ('".addentities($_SESSION['nume'])."','".addentities($_SESSION['prenume'])."','".addentities($_SESSION['nr'])."','".addentities($_SESSION['cnp'])."','".addentities($_SESSION['mail'])."','".addentities($_SESSION['locmunca'])."')";
}

我尝试使用弹出窗口 alert (echo "<script>alert('Something's wrong')</script>";在 if 子句之后)但它没有用..

Answer 1

您需要检查，是否设置了发布数据，如果是，则将其设置为输入值。例如:

<tr><td>Nume: <th><input type="text" name="nume" value="<?php if (!empty($_POST["nume"])) { echo $_POST["nume"]; } else { echo ''; };  ?>" required></th></td></tr>