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<html>
<head><title>管理界面</title>
<link href="xinfei.css" rel="stylesheet" type="text/css">
<!--引用刚定义的样式表xinfei.css-->
</head>
 <body>
<div align="center" class="text01">管理界面
<hr width="600" size="1" color=red>
<form action="manage.php" method="post" name="form1" class="text01">      <table width="600" border="0" cellspacing="0" cellpadding="0">
      <tr>
          <td width="135">&nbsp;</td> 
          <td width="22">&nbsp;</td>  
          <td width="443">&nbsp;</td>  
     </tr>
        <tr>   
            <td class="text01">
   <div align="right">网上调查的标题</div></td>
         <td>&nbsp;</td>
         <td><input name="title" type="text" class="form01" size="60"></td>
         </tr>
        <tr>
            <td class="text01">
      <div align="right"></div></td>
             <td>&nbsp;</td>
             <td>&nbsp;</td>
         </tr>
       <tr>
          <td class="text01">
      <div align="right">第一项</div></td>
              <td>&nbsp;</td>
              <td><input name="option1" type="text" class="form01" size="60"></td>
   </tr>
    <tr>
     <td class="text01">
  <div align="right"></div></td>
            <td>&nbsp;</td>
            <td>&nbsp;</td>
            </tr>
           <tr>
              <td class="text01">
     <div align="right"></div></td>
              <td>&nbsp;</td>
             <td>&nbsp;</td>
         </tr>
       <tr>
           <td class="text01">
     <div align="right">第二项</div></td>
              <td>&nbsp;</td>
              <td><input name="option2" type="text" class="form01" size="60"></td>
   </tr>
    <tr>
     <td class="text01">
  <div align="right"></div></td>
            <td>&nbsp;</td>
            <td>&nbsp;</td>
            </tr>
           <tr>
              <td class="text01">
     <div align="right"></div></td>
              <td>&nbsp;</td>
             <td>&nbsp;</td>
         </tr>
       <tr>
           <td class="text01">
   <div align="right">第三项</div></td>
              <td>&nbsp;</td>
              <td><input name="option2" type="text" class="form01" size="60"></td>
   </tr>
    <tr>
     <td class="text01">
  <div align="right"></div></td>
            <td>&nbsp;</td>
            <td>&nbsp;</td>
            </tr>
           <tr>
              <td class="text01">
      
   <div align="right">第四项</div></td>
              <td>&nbsp;</td>
              <td><input name="option4" type="text" class="form01" size="60"></td>
   </tr>
    <tr>
            <td>&nbsp;</td>
            <td>&nbsp;</td>
            <td>&nbsp;</td>
              <td>&nbsp;</td>
             <td>&nbsp;</td>
            </tr>            
       <tr class="text01"> 
                <td colspan="3"> 
                   <div align="center">
                       <input type="radio" name="choice" vlaue="addone">
                         添加
                       <input type="radio" name="choice" value="deleone">
                         删除</div></td>
               </tr>
             <tr class="text01">
                <td>&nbsp;</td>
                <td>&nbsp;</td>
                <td>&nbsp;</td> 
                <td>&nbsp;</td> 
             </tr>
           <tr>
               <td colspan="3"><div align="center">
              <hr width="600" size="1" color=red>
                     <input type="submit" name="ok" value="提交">
                     <input type="reset" name="Submit2" value="重写">
               </div></td>
            </tr>
            <tr>
                <td>&nbsp;</td>
                <td>&nbsp;</td>
                <td>&nbsp;</td>
            </td>
          </table>
         </form>
         </div>
             </body>
</html>
  <?php
     include "common.inc.php";
    if($ok)
    {
     if($choice='addone')
      {
       if($title=="")
          {header("location:error.php?error=调查标题不能为空");
          exit;
          }
        if(($option1=="")||($option2==""))
        {
          {header("location:error.php?error=调查前两项不能为空");
           exit;
        }
        $n=2;
         if($option3!="")$n++;//n=3
         if($option4!="")$n++;//n=4
             $sql="select title from survey where title='$title'";
                @$a=mysql_query($sql)or die(";错误 1");
              $check_num=mysql_numO_rows($a);
               if($check_num==0)
                  {
             $sql="insert into survey values('$title','$n','$option1','$option2','$option3','$option4',1,1,1,1)";
                    @mysql_query($sql)or die("无法添加调查项目");
                    header('location:ok.php?ok_info=成功添加调查项目');
                  }      }
      if($choice=='deleone')
          {
              $sql="select title from survry where title='$title'";
              @$a=mysql_query($sql) or die("错误 2");
              $check_num=mysql_num_rows($a);
              if($check_num==0)
              {
                header("location:error.php?error=您要删除的项目不存在");
              }
              else
              {}
            $b='delete from survey where title="$title"';
            mysql_query($b) or die("呵呵 不能删除啊");
            header('location:ok.php?ok_info=您已经成功删除所选项目');
          }
    }
    }
?>
    这段代码 header("location:error.php?error=您要删除的项目不存在");怎么提示有错呢！  还有 有什么语法 逻辑问题 请多多指教小弟啊！！！