在按钮单击后从下拉列表中保存最后选择的值 - Keeping lastly selected value from a dropdownlist after button click

Keeping lastly selected value from a dropdownlist after button click

就像标题所说的那样，我很难做到。

下面是我的下拉列表:

<?php
      $query = "SELECT data, rel_id FROM $tbl_rel_balansas INNER JOIN $tbl_balansas ON $tbl_rel_balansas.rel_id = $tbl_balansas.id WHERE $tbl_rel_balansas.member_id = '$_SESSION[id]' group by data";
      $result = mysql_query ($query);
      echo "<select name=data value=''>Data</option>";
      while($nt=mysql_fetch_array($result)){
        echo "<option value=$nt[data] name='"blabla'">$nt[data]</option>";
      }
      echo "</select>";
?>

这是按钮:

<?php
      if(isset($_POST['Submit']))
      {
        $query = "SELECT SUM(suma), paskirtis FROM $tbl_rel_balansas INNER JOIN $tbl_balansas ON $tbl_rel_balansas.rel_id = $tbl_balansas.id WHERE $tbl_rel_balansas.member_id = '$_SESSION[id]'  AND data ='".$_POST['data']."' group by paskirtis";
        $result = mysql_query ($query);
        echo "<tr><td>Paskirtis:</td><td>Biudzetas:</td><td>Isleista:</td><td>Likutis:</td></tr>";
        while($nt=mysql_fetch_array($result)){
            if($nt['SUM(suma)'] != null){
            $suma = $nt['SUM(suma)'];
        }
            echo "<tr><td>$nt[paskirtis]</td>
            <td><input type='"text'" name='"isleista[]'" value='"Skiriamų pinigų kiekis...'" method='"post'"></td><td>".$suma." Lt</td><td>--</td></tr> <br>";
        }
      }
?>

在我按下它之后，它从我从下拉列表中选择的日期中检索我想要的数据，并且还重置整个下拉列表，显示sql数据库中日期的第一个值，而不是我选择的那个。如果有人知道如何在列表中保持所选值，任何帮助都非常感谢!

试试这个，您需要将select="selected"放在while循环中。看看下面的代码我是如何放置$selected

的

<?php
      $query = "SELECT data, rel_id FROM $tbl_rel_balansas INNER JOIN $tbl_balansas ON $tbl_rel_balansas.rel_id = $tbl_balansas.id WHERE $tbl_rel_balansas.member_id = '$_SESSION[id]' group by data";
      $result = mysql_query ($query);
      echo "<select name=data value=''>Data</option>";
      while($nt=mysql_fetch_array($result)){
        $selected = ($_POST['blabla'] == $nt[data])?'selected="selected"':NULL;
            echo "<option value=$nt[data] name='"blabla'" $selected >$nt[data]</option>";
      }
      echo "</select>";
?>