Php var_dump中显示的空字段

我正在尝试更新产品的所有字段，除了produt name字段

下面是我的var_dump

string 'UPDATE product SET

`discription` = 'sasasaas',

`product_name` ='',

category_id = 14,

price=10000,

first_price=1000,

second_price=1000,

third_price=10000,

fourth_price=10000,

total_discount=10000,

product_quantity_discount=10000,

weight=10000,

dimension=1000,

`shipping_class`='sasasas',

stock_quantity=1000,

`stock_status`='inorder',

`back_order`='ALLow'

WHERE product_id = 13' (length=511)

我的问题是，为什么我会收到产品_name=”“empty

这是我的代码

  <label for="exampleInputEmail1">Product Name</label>
  <input type="text" name="product_name" class="form-control" value="<?php   
  echo($row['product_name']);?>">


$this->product_discription = trim ( mysql_prep ( $_POST ['discription'] ) );
    $this->category_id = mysql_prep ( $_POST ['data_category'] );
    $this->regular_price = trim ( mysql_prep ( $_POST ['regular_price'] ) );
    $this->price1 = trim ( mysql_prep ( $_POST ['price1'] ) );
    $this->price2 = trim ( mysql_prep ( $_POST ['price2'] ) );
    $this->price3 = trim ( mysql_prep ( $_POST ['price3'] ) );
    $this->price4 = trim ( mysql_prep ( $_POST ['price4'] ) );
    $this->total_discount = trim ( mysql_prep ( $_POST ['total_discount'] ) );
    $this->product_qantity_discount = trim ( mysql_prep ( $_POST ['quantity_discount'] ) );
    $this->weight = trim ( mysql_prep ( $_POST ['weight'] ) );
    $this->dimension = trim ( mysql_prep ( $_POST ['dimension'] ) );
    $this->shipping_class = trim ( mysql_prep ( $_POST ['shipping'] ) );
    $this->stock_quantity = trim ( mysql_prep ( $_POST ['stock'] ) );
    $this->stock_status = mysql_prep ( $_POST ['stock_status'] );
    $this->back_order = mysql_prep ( $_POST ['back_order'] );
    $this->product_name =  mysql_prep ( $_POST ['product_name'] ) ;
    $this->id = $_GET ['id'];

    $this->sql = "UPDATE product SET

                        `discription` = '{$this->product_discription}',
                        `product_name` ='{$this->product_name}',
                        category_id = {$this->category_id},
                        price={$this->regular_price},
                        first_price={$this->price1},
                        second_price={$this->price2},
                        third_price={$this->price3},
                        fourth_price={$this->price4},
                        total_discount={$this->total_discount},
                        product_quantity_discount={$this->product_qantity_discount},
                        weight={$this->weight},
                        dimension={$this->dimension},
                        shipping_class='{$this->shipping_class}',
                        stock_quantity={$this->stock_quantity},
                        stock_status='{$this->stock_status}',
                        back_order='{$this->back_order}'
                        WHERE product_id = {$this->id}";

      mysql_query($this->sql);
      confirm_query($this->sql);
    echo    var_dump($this->sql ,TRUE);

产品名称
您似乎在此处输入了一个错误：

$this->produt_name

除了您在$this->produt\u name中拼写产品错误之外，尽管它看起来是一致的
var\u dump（$\u POST['product\u name']）
？字符串“”（长度=0）空字符串！！因此，您发布的值是空的（它与MySQL或PHP无关（除非您取消设置此值））。你确定你在填写吗？您确定字段的名称正确吗？请查看您的网络选项卡。字段设置正确且html正确evey feild是正确的，但我没有得到产品名称字段字符串“”（长度=0）空字符串您检查了帖子数据吗？
$\u POST['product\u name']
中有什么内容？POST数据中有一个空字段。您确定没有其他html格式的名为
product\u name
的元素吗？