如何根据来自数据库的值更改选择标签值

Question

我想基于来自database.if的值更改标记选项。如果值是“ 1”，我想显示不同的选项，而其他值则不同。

<<!DOCTYPE html>
    <html>
    <head>
        <title>select</title>
    </head>
    <?php

    if(isset($_POST['submit']))
    {

        $number=$_POST['number'];
        //echo $number;
    if ($number=="1")
    { 

         echo "<select name='subject'>
         <option  value='1'>chemistry</option>
         <option  value='2'>Physics</option>
         <option  value='3'>Biology</option>
         <option  value='4'>Maths</option></select>"
    }
    else
    {
    echo "<select name='subject'>
          <option  value='5'>english</option>
          <option  value='6'>computer</option>
          <option  value='7'>Biology</option>
          <option  value='8'>Maths</option></select>"
    }
    ?>
    <body>
    <form method="post" action="select.php"> 
    <input type="text" name="number" value="">
    <input type="submit" name="submit" value="submit">
    </form>
    </select>
    </body>
    </html>

Answer 1

因为

没有关门; 在这里<option value='4'>Maths</option></select>"
这里也是<option value='8'>Maths</option></select>"
首先， if()条件缺少结尾} 。

所以最终的代码是

<!DOCTYPE html>
<html>
<head>
    <title>select</title>
</head>
<?php

    if(isset($_POST['submit']))
    {

        $number = $_POST['number'];
        //echo $number;
        if ( $number == "1" )
        {

            echo "<select name='subject'>
         <option  value='1'>chemistry</option>
         <option  value='2'>Physics</option>
         <option  value='3'>Biology</option>
         <option  value='4'>Maths</option></select>";
        }
        else
        {
            echo "<select name='subject'>
          <option  value='5'>english</option>
          <option  value='6'>computer</option>
          <option  value='7'>Biology</option>
          <option  value='8'>Maths</option></select>";
        }
    }

?>
<body>
<form method="post" action="select.php">
    <input type="text" name="number" value="">
    <input type="submit" name="submit" value="submit">
</form>
</select>
</body>
</html>

Answer 2

你错过了; 两个回声的结尾：

if(isset($_POST['submit']))
{

    $number=$_POST['number'];
    //echo $number;
    if ($number=="1")
    { 

         echo "<select name='subject'>
         <option  value='1'>chemistry</option>
         <option  value='2'>Physics</option>
         <option  value='3'>Biology</option>
         <option  value='4'>Maths</option></select>";
    }
    else
    {
          echo "<select name='subject'>
          <option  value='5'>english</option>
          <option  value='6'>computer</option>
          <option  value='7'>Biology</option>
          <option  value='8'>Maths</option></select>";
     }
}
?>

注意：很抱歉布局不佳，答案很快发布！

Answer 3

if(isset($_POST['submit']))
{
    $number=$_POST['number'];
    //echo $number;
    if ($number=="1")
    { 

        echo "<select name='subject'>
        <option  value='1'>chemistry</option>
        <option  value='2'>Physics</option>
        <option  value='3'>Biology</option>
        <option  value='4'>Maths</option></select>"; //missing ; here
    }
    else
    {
        echo "<select name='subject'>
        <option  value='5'>english</option>
        <option  value='6'>computer</option>
        <option  value='7'>Biology</option>
        <option  value='8'>Maths</option></select>";  //missing ; here
    }
}  // missing } here

如何根据来自数据库的值更改选择标签值

问题描述

3 个解决方案

解决方案1
1 已采纳 2015-09-11 10:45:57

解决方案2
0 2015-09-11 10:44:57

解决方案3
0 2015-09-11 10:45:55

如何根据来自数据库的值更改选择标签值

问题描述

3 个解决方案

解决方案1 1 已采纳 2015-09-11 10:45:57

解决方案2 0 2015-09-11 10:44:57

解决方案3 0 2015-09-11 10:45:55

解决方案1
1 已采纳 2015-09-11 10:45:57

解决方案2
0 2015-09-11 10:44:57

解决方案3
0 2015-09-11 10:45:55