Php CodeIgniter：根据选择的第一个选择选项，尝试从数据库表加载选项值

我正在使用CodeIgniter，有一个带有2个选择选项的表单。第一个选择选项是汽车品牌，第二个选择选项是品牌。如果我从“BMW”中选择汽车品牌，则第二个选择选项中的值应更改并显示BMW制造的所有车型

**WelcometoDemoCar.php (View)**

*//to get the Car Make List Box*

<input type = "text" name = "car_list" list="car_dalalist" id = "car_list" class = "inktext inklarge" placeholder = "Type of Car" required = "" autocomplete="off" />
<datalist id="car_dalalist">
 <?php foreach($carlist as $row_carlist){?>
<?php //echo $row_carlist->Make . " " .$row_carlist->Model ." " .$row_carlist->Year ;?>
<option value="<?php echo $row_carlist->Make;?>"> <?php echo $row_carlist->Make;?></option>
<?php }?> 
</datalist>


*//to get the value in the Make Select List Box*


<input type = "text" name = "car_model" list="car_model_dalalist" id = "car_model" class = "inktext inklarge" placeholder = "Car Model" required = <datalist id="car_model_dalalist">
<?php foreach($carModel as $row_carModel){?>
<?php //echo $row_carlist->Make . " " .$row_carlist->Model ." " .$row_carlist->Year ;?>
<option value="<?php echo $row_carModel->Model;?>"><?php echo $row_carModel->Model;?> </option>
<?php }?> 
</datalist> 


**Welcome.php (Controller)**

$this->data['carlist'] = $this->PostModel->getCarDetails(); 
$this->data['carModel'] = $this->PostModel->getCarModel();

**PostModel.php (Model)**



*//to get car make*

 function getCarDetails(){
  $this->db->Distinct();
  $this->db->select("Make"); 
  $this->db->from('carlist');
  $carListquery = $this->db->get();
  return $carListquery->result();
 }


 *// to get car model*


 function getCarModel(){
  $make = $this->input->post('car_list');   

  $this->db->Distinct();
  $this->db->select("Model"); 
  $this->db->from('carlist');
  $this->db->where('Make' . $make);
  $carmodelquery = $this->db->get();
  return $carmodelquery->result();
 }


public function get_data()
 {
      $value = $this->input->post("value");
      $data = $this->PostModel->get_data($value);
      $option ="";
      foreach($data as $d)
      {
         $option .= "<option value='".$d->id."' >".$d->Model."</option>";
      }
       echo $option;
 }

非常感谢你的时间和帮助

提前感谢。

请更新数据：{value:'value'}，数据：{value:value}

---

从value中删除单引号

关于代码有几个问题。 未来参考：见OP帖子上的评论

主要问题是单击处理程序：

    $("#car_list").on("change",function(){ 
     var value = $(this).val(); 
     $.ajax({ url : "welcome/get_data", 
     type: "post", 
     data: {"value":value}, //OP originally used single quotes on the value therefore passing a string instead of the actualy variable

     success : function(data){ 
     $("#car_model").html(data); 
     }, 
     });
     });

控制器和模型的问题

---

@你能分享你的ajax吗code@Abhijit我已经更新了我的ajax代码，但该车列表并未以表格形式出现。另外，get_数据不存在于您的代码中provided@Abhijit对不起，我的错。。元素名称和ID为car_list。其在模型和控制器中与car_列表相同。我现在将更新我的code@Abhijit我刚刚更新了问题中的代码。很抱歉我将其从value改为car_list，但仍然没有显示在下拉列表中。您能看到AJAX调用被触发，请求中为其发布了什么值吗？

    $("#car_list").on("change",function(){ 
     var value = $(this).val(); 
     $.ajax({ url : "welcome/get_data", 
     type: "post", 
     data: {"value":value}, //OP originally used single quotes on the value therefore passing a string instead of the actualy variable

     success : function(data){ 
     $("#car_model").html(data); 
     }, 
     });
     });

 public function get_data()
 {
      $data = $this->PostModel->get_data(); //OP originally passed $value to the model but $value does not exist
      $option ="";

      if(count($data) > 0){
          foreach($data as $d)
          {
             $option .= "<option value='".$d->Model."' >".$d->Model."</option>";
          }
          echo $option;
      }

 }