我要选择一个表，并创建一个表，从表中的相同数据，我选择

Question

这是我的问题：

1. 我从两个选择的值下拉列表中就会变回其默认值为 当浏览器在窗体中实现函数onchange时。

2. 我想创建一个表格，数据应该与我从第二个下拉列表中选择的表格 相同。

这是我的代码

PHP

<?php 
    $connectDatabase = mysql_connect("localhost","root","") or die(mysql_error()); 
    $tables = array(); 
    if(isset($_POST['select_db'])) 
    { // if its submitted 
     $select_db = $_POST['select_db']; 
     $mysql_select_db = mysql_select_db($select_db,$connectDatabase); 
     $drop_table = mysql_query("DROP TABLE pdf_table",$connectDatabase); 
     $query = "SHOW TABLES FROM $select_db"; 
     $mysql_query = mysql_query($query,$connectDatabase); 
     while($row =mysql_fetch_assoc($mysql_query)) 
     { 
      $tables[] = $row['Tables_in_' . $select_db]; // use associative instead 
     } 
    } 
    if(isset($_POST['select_table'])) 
    { 
     $select_table = $_POST['select_table']; 
     $db = mysql_select_db($select_db,$connectDatabase); 
     $query_select = "Create Table pdf_table AS (SELECT * FROM $select_table)"; 
     $select_query = mysql_query($query_select,$connectDatabase); 
    } 
    ?> 

HTML代码

<form class="Search_Form" action="moduleindex.php" method="POST"> 
     <select name="select_db" onchange="this.form.submit();"> 
      <option disabled selected>Select Database</option> 
      <option>section_masterfile</option> 
     </select> 
     <select onchange="this.form.submit();" name="select_table"> 
      <option disabled selected>Select Table</option> 
      <?php foreach($tables as $table): ?> 
      <option value="<?php echo $table; ?>"><?php echo $table; ?></option> 
      <?php endforeach; ?> 
     </select> 
</form> 

Answer 1

添加支票foreach循环而产生的选项，如果某个值发布和价值等于t Ø循环值

<select onchange="this.form.submit();" name="select_table"> 
       <option disabled selected>Select Table</option> 
       <?php foreach($tables as $table){?> 
       <?php 
       $selected =""; 
       if(isset($_POST['select_table']) && $_POST['select_table'] == $table){ 

         $selected = 'selected="selected"'; 


        } ?> 
       <option value="<?php echo $table; ?>" <?php echo $selected ;?> ><?php echo $table; ?></option> 
       <?php }?> 
      </select>