我正在制作一份报告，我需要按类别过滤详细信息。我的 itr 表中有两个类别，分别是 Resident 和 4Ps。

到目前为止，这是我的代码。我可以在这里打印 itr 表的所有详细信息。

<table>
  <tr>
    <th style = "padding-right:80px;padding-left:150px;">
    <center>Name</center></th>
    <th style = "padding-right:10px;padding-left:15px;"><center>Age</center>
    </th>
    <th style = "padding-right:10px;padding-left:20px;">
    <center>Gender</center></th>
    <th style = "padding-right:30px;padding-left:40px;">
    <center>Purok</center></th>
 </tr>
 <?php
   $query = $conn->query("SELECT * FROM itr LIMIT 30") or 
   die(mysqli_error());
   for($a = 1; $a <= 30; $a++){
     $fetch = $query->fetch_array()
 ?>
<tr>
  <td><?php echo $a.". ".$fetch['firstname']." ".$fetch['firstname']?></td>
  <td><center><?php echo $fetch['age']?></center></td>
  <td><center><?php echo $fetch['gender']?></center></td>
  <td><center><?php echo $fetch['address']?></center></td>
</tr>
<?php
}
$conn->close();
?>

我想要的是使用“按类别过滤”之类的按钮仅打印 4Ps 类别中的那些人，我可以在其中选择按居民或 4Ps 进行过滤，以便我只能使用一个 php 文件。我不知道该怎么做。请帮助:)

这是类别的html

<label for = "category">Please select category:</label>
    <select style = "width:22%;" class = "form-control" name = "category" required = "required">
        <option value = "">--Select category--</option>
        <option value = "RESIDENT">RESIDENT</option>
        <option value = "4Ps">4Ps</option>
    </select>
<br />

这是我的 itr 表:

这是我想要的输出:

最佳答案

1.你需要把category-select-box放到一个form里面

2.当用户根据即将到来的类别提交表单时，需要更改查询。

像下面这样:-

<form method="POST">

    <label for = "category">Please select category:</label>
    <select style = "width:22%;" class = "form-control" name = "category" required = "required">
        <option value = "">--Select category--</option>
        <option value = "RESIDENT">RESIDENT</option>
        <option value = "4PS">4Ps</option> <!-- changed option value to capitals-->
    </select>
    <input type="submit" name="submit" value="submit">
</form>

<table>
  <tr>
    <th style = "padding-right:80px;padding-left:150px;">
    <center>Name</center></th>
    <th style = "padding-right:10px;padding-left:15px;"><center>Age</center>
    </th>
    <th style = "padding-right:10px;padding-left:20px;">
    <center>Gender</center></th>
    <th style = "padding-right:30px;padding-left:40px;">
    <center>Purok</center></th>
 </tr>
 <?php
   if(isset($_POST['category']) && $_POST['category'] !==''){
    $category = $_POST['category'];
    $query = $conn->query("SELECT * FROM itr where category = '$category' LIMIT 30") or die(mysqli_error());
   }else{
    $query = $conn->query("SELECT * FROM itr LIMIT 30") or die(mysqli_error());
   }
   for($a = 1; $a <= 30; $a++){
     $fetch = $query->fetch_array()
 ?>
<tr>
  <td><?php echo $a.". ".$fetch['firstname']." ".$fetch['firstname']?></td>
  <td><center><?php echo $fetch['age']?></center></td>
  <td><center><?php echo $fetch['gender']?></center></td>
  <td><center><?php echo $fetch['address']?></center></td>
</tr>
<?php
}
$conn->close();
?>

注意:-您的代码对 SQL 注入(inject)是开放的。为了防止它使用 prepared statements

引用:-

mysqli prepared statements

PDO prepared statements

关于php - 按类别过滤以在 php 中打印，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/48223089/