根据第一个下拉列表填充下拉列表

Question

我想在从部门下拉框中选择一个部门后填充 whoom-to-meet 下拉框，但是当我点击部门列表时，所有部门都会显示，但是当我选择一个部门时，该部门的相关员工未显示在 whoom-to-meet 下拉列表中。下面是我的两张表。 部门表

+----+-----------+
| id | dept_name |
+----+-----------+
|  2 |    hr     |
+----+---------- +

user_master 表

+----+-------------+-----------+----------+
| id |  emp_name   |  dept_id  |   type   |
+----+-------------+-----------+----------+
| 1  |   dipti     |     2     | employee |
+ ---+-------------+-----------+----------+

我的控制器

public function create_pass() {
    $pageid = 1;
    $data['hh'] = $this->admin_model->get_dept();
    $this->load->view('header');
    $this->load->view('sidebar');
    $this->load->view('createpass', $data);
    $this->load->view('footer');
}   

public function select_item_by_dept() {
    if ($this->session->userdata('admin_logged_in')) {
        $category_id = $this->input->post('category_id');
        $data['result'] = $this->admin_model->select_item_by_cat($category_id);

        $HTML = "";            
        foreach ($data['result'] as $list) {
            $HTML.="<option value='" . $list['dept_id'] . "'>" . $list['emp_name'] . "</option>";
        }           
        echo $HTML;
    } else {
        $this->load->view('login');
    }
}

我的模特

function select_item_by_cat($category_id) {
    $this->db->where('dept_id', '$category_id');
    $query = $this->db->get('user_master');
    return $query->result_array();
}
function get_dept() {
    $this->db->select("*");
    $this->db->from('department');
    $query = $this->db->get();
    return $query->result_array();
}

我的看法

<div class="form-group">
  <label for="inputPassword3" class="col-sm-3 control-label">Department to go </label>
  <div class="col-sm-3">
    <select class="form-control select2" name="dptgo" id="dptogo" onchange="change_category(this.options[this.selectedIndex].value)" style="width: 100%;">
      <option selected="selected">Select</option>                                                    
      <?php foreach($hh as $datas)
      { ?>
        <option value="<?php echo $datas['id']; ?>"><?php echo $datas['dept_name']; ?></option>
<?php } ?>
    </select>
    <div class="text-danger"><?php echo form_error('dptgo'); ?></div>
  </div>
  <label for="inputPassword3" class="col-sm-2 control-label">Whom to Meet</label>
  <div class="col-sm-4">
    <select class="form-control select2" id="whomtmt" name="wtomeet" style="width: 100%;">
      <option selected="selected">Select</option>
      <option></option>
    </select>
  </div>
</div>

我的 jquery

<script>
  function change_category(category_id) {
    if (category_id == "Select") {
      $("#whomtmt").html("<option>Select</option>");
      $("#whomtmt").trigger("chosen:updated");
      $("#whomtmt").trigger("liszt:updated");
    } else {
      loadData(category_id);
    }
  }
  function loadData(category_id) {
    var dataString = 'category_id=' + category_id;
    $.ajax({
      type: "POST",
      url: "<?php echo site_url(); ?>/admin/select_item_by_dept",
      data: dataString,
      cache: false,
      success: function (result) {
        $("#whomtmt").html("<option>Select</option>");
        $("#whomtmt").append(result);
        $("#whomtmt").trigger("chosen:updated");
        $("#whomtmt").trigger("liszt:updated");
      }
    });
  }
</script>

Answer 1

在你的模型中，在 select_item_by_cat 函数中

这是错误的$this->db->where('dept_id', '$category_id');

查询是这样执行的

SELECT * FROM `user_master` WHERE `dept_id` = '$category_id'

所以改成

$this->db->where('dept_id', $category_id);

尝试一下对你有帮助:)