我创建了一个动态下拉列表,它从数据库中填充数据。直到现在它工作正常。现在我想将下拉列表中的选定数据添加到我的数据库中。我尝试了各种可能的方法,但无法在我的数据库中插入值,以下程序没有给出任何错误消息,但它也没有在我的数据库中插入数据。请检查一下。
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<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>
<body>
</body>
</html>
<?php 
session_start();
if(isset($_SESSION['username']))
{
    include 'connect.php';
            $select_query=          'Select * from category';
            $select_query_run =     mysql_query($select_query);
    echo "  
        <form action='insert_product.php' method='POST' ></br>
        Product Name:   <input type='text' name='product_name'  /></br>
        Price       :   <input type= 'text' name= 'price'  /></br>
        Description :   <input type='text' name='description'  />*Seperate by Comma</br>
                        ";
    //  Drop Down Display   
            echo "<select name='category'>";
            while   ($select_query_array=   mysql_fetch_array($select_query_run) )
            {
                    echo "<option value='".$select_query_array['category_id']."' >".
                    htmlspecialchars($select_query_array["name"])."</option>";
                }
         $selectTag= "<input type='submit' value='Insert'  /></select></form>";
         echo $selectTag;
    //Drop Down End!
    if(isset($_POST['product_name']) && isset($_POST['price']) && isset($_POST['description'])  )
    {
        echo $product_name  =       $_POST['product_name'];
        echo $price         =       $_POST['price'];
        echo $description   =       $_POST['description'];
        echo $category      =       $_POST['category'];
//Problem Area 
    $query= "insert into products (name, price, description,  category_id ) 
                VALUES( '$product_name', $price, '$description', $category )";
    if($query_run=      mysql_query($query))
    {
        echo 'Data Inserted';
        }   
        else
        {
            'Error In SQL'.mysql_error();
            }
    }
    else
    {
        echo 'empty Field';
        }
}
else
{
    echo 'You Must Log in To View this Page!';
    }
?>