页面刷新时文字消失了吗？ （铬）

Question

我有一个html页面，链接到一个php函数页面，上面有很多函数。 看来，当在Chrome中单击刷新按钮时，文本（仅来自功能）消失。为什么会造成这种情况？这与执行元刷新的更新按钮相同......

function Add_Remove_Topics(){
//CONECT TO MYSQL
$username = "root";
$password = "";
$database = "user_test";
$id = ($_SESSION["user_id"]);

$connect = mysql_connect('localhost',$username,$password);
@ mysql_select_db($database) or die( "Unable to select database");

//GET VALUES
    $sql = "SELECT * FROM topics";
    $result = mysql_query($sql);

//echo "<div id='add-remove-topics'>";
        //Table headlines - NOT A PHP

        echo "<center>Simply type into the fields to change your current topic information - click update once done editing. If you no longer want one of your topics, click the delete button.</center>";

        echo "<form action='' method='POST'><table id='artopics'>
                <col width='30%'>
                <col width='70%'>
                <col width='70px'>
                <col width='70px'>
                <tr height='40px'>
                    <td style='background-color: #BD4040; color: white; padding-left: 5px;'>Topic Name</td>
                    <td style='background-color: #BD4040; color: white; padding-left: 5px;'>Topic Address</td>
                    <td style='background-color: #BD4040;'></td>
                    <td style='background-color: #BD4040;'></td>
                </tr>";

        // output data of each row

        while($row = mysql_fetch_assoc($result)) 
        {


                echo 
                "
                    <tr height='40px'>
                        <td align='center' style='font-weight: normal;background-color: white;'><input type='text' name='up_topic_name[{$row['topic_id']}]' value='" . $row['topic_name'] . "'></td>
                        <td align='center' style='font-weight: normal;background-color: white;'><input type='text' name='up_topic_address[{$row['topic_id']}]' value='" . $row['topic_address'] . "'></td>
                        <td style='background-color: white;' align='center'><button type='submit' name='updateTopic' value='".$row['topic_id']."'>Update</button></td>
                        <td style='background-color: white;' align='center'><button type='submit' name='deleteTopic' value='".$row['topic_id']."'>Delete</button></td>
                    </tr>

                ";



            }

            if(isset($_POST['updateTopic'])){
                $updateID = $_POST['updateTopic'];
                $updateTopicName = $_POST['up_topic_name'][$updateID];
                $updateTopicAddress = $_POST['up_topic_address'][$updateID];
                $updateTopic = mysql_query("UPDATE topics SET topic_name='$updateTopicName', topic_address='$updateTopicAddress' WHERE topic_id='$updateID'") or die(mysql_error());
                echo "<meta http-equiv='refresh' content='0'>";
            }


            if(isset($_POST['deleteTopic'])){
                $deleteID = $_POST['deleteTopic'];
                $deleteFromTopics = mysql_query("DELETE FROM topics WHERE topic_id = $deleteID ") or die(mysql_error());
                $deleteFromUserTopic = mysql_query("DELETE FROM user_topic WHERE topic_id = $deleteID ") or die(mysql_error());
                echo "<meta http-equiv='refresh' content='0'>";
            }

        echo "</table></form>";


        echo "<br><center>To add a new topic, simply fill in the fields below, clicking insert once completed.</center>";

        echo "<form action='' method='POST'><table id='artopics'>
                <col width='30%'>
                <col width='70%'>
                <col width='140px'>
                <tr height='40px'>
                    <td style='background-color: #BD4040; color: white; padding-left: 5px;'>Topic Name</td>
                    <td style='background-color: #BD4040; color: white; padding-left: 5px;'>Topic Address</td>
                    <td style='background-color: #BD4040;'></td>
                </tr>";

        // output data of each row



                echo 
                "
                    <tr height='40px'>
                        <td align='center' style='font-weight: normal;background-color: white;'><input type='text' name='new_topic_name'></td>
                        <td align='center' style='font-weight: normal;background-color: white;'><input type='text' name='new_topic_address'></td>
                        <td align='center' style='background-color: white;'><button style='width:130px;' type='submit' name='InsertTopic'>Insert</button></td>
                    </tr>

                ";






            if(isset($_POST['InsertTopic'])){
                $topicName = $_POST['new_topic_name'];
                $topicAddress = $_POST['new_topic_address'];
                $insertIntoTopics = mysql_query("INSERT INTO topics (topic_name, topic_address) VALUES ('$topicName', '$topicAddress') ") or die(mysql_error());
                $grabNewTopicId = mysql_query("SELECT MAX(topic_id) AS topic_id FROM topics") or die(mysql_error());
                while($row2 = mysql_fetch_array($grabNewTopicId)) {
                    $NewTopicId = $row2['topic_id'];
                    $insertIntoUserTopic = mysql_query("INSERT INTO user_topic (user_id, topic_id) VALUES ('$id', '$NewTopicId') ") or die(mysql_error());
                }
                echo "<meta http-equiv='refresh' content='0'>";

            }

        echo "</table></form>";
        }

（包括截图）

Before refresh/button click

After refresh/button click