提交后不重置表单值

Question

通过php头部代码预览后，我想不重置输入框？谢谢。 这是我的简化代码：

#php Code 
if($_POST['pre']){ 

    $tag = $_POST['tag']; 
    $link = $_POST['link']; 
    $img = $_POST['img']; 
    $exp = $_POST['exp']; 
    $alt = $_POST['alt']; 
    if ($tag == '' or $img == '' or $alt==''){ 

    } 
    else{ 
    $_SESSION['pre'] = "<a href=" ; 
    $_SESSION['pre'] .= "\"$link\"><img src="; 
    $_SESSION['pre'] .= "\"$img\" alt=\"$alt\" ></a>"; 
    header("location: add_adv.php?show=on"); 
    } 
} 

HTML代码

<table> 
<tr><td id="title"><p>add</p></td></tr> 
<tr><td></td></tr> 
    <tr> 
     <td><form name="form2" method="post" action=""> 
     <table> 
      <tr> 
      <td><input type="text" name="tag" id="tag" /> </td> 
      <td>tag</td> 
      </tr> 
      <tr> 
      <td><input type="text" size="30" name="img" id="img" /></td> 
      <td>picture</td> 
      </tr> 
      <tr> 
      <td><input type="text" size="30" name="link" id="link" /></td> 
      <td>link</td> 
      </tr> 
      <tr> 
      <td><input type="text" size="30" name="alt" id="alt" /></td> 
      <td>alternative</td> 
      </tr> 
      <tr> 
      <td><input type="text" size="30" name="exp" id="exp" /></td> 
      <td>Expire</td> 
      </tr> 
      <tr> 
      <td><input name="pre" type="submit" class="sub" id="pre" value="Preview"> 
       <input type="submit" name="add_adv" class="sub" id="add_adv" value="اضافه" /></td> 
      <td></td> 
      </tr> 
    </table> 
     </form> 
</td> 
    </tr> 
    </table> 

Answer 1

你必须给所有的输入框属性的值等于先前提交的值。

<td><input type="text" size="30" name="exp" id="exp" value="<?=$exp?>" /></td> 
<td>Expire</td> 

Answer 2

// make public 
$tag = $link = $img = $exp = $alt = null; 

if($_POST['pre']){ 

    $tag = $_POST['tag']; 
    $link = $_POST['link']; 
    $img = $_POST['img']; 
    $exp = $_POST['exp']; 
    $alt = $_POST['alt']; 
    if ($tag == '' or $img == '' or $alt==''){ 

    } 
    else{ 
    $_SESSION['pre'] = "<a href=" ; 
    $_SESSION['pre'] .= "\"$link\"><img src="; 
    $_SESSION['pre'] .= "\"$img\" alt=\"$alt\" ></a>"; 
    header("location: add_adv.php?show=on"); 
    } 
}