php - 在 codeigniter 中使用 mpdf 为 foreach() 提供的参数无效

Question

当我尝试编辑我的 where 条件时，我在 codeigniter 的模型文件中收到警告说 Invalid argument supplied for foreach()。

其实我想根据外键加载记录。

当我添加这行代码时，$this->db->where('project.id',$id);在模型中，我收到上述错误。

Controller 文件

<?php

class Createpdf extends CI_Controller {

public function __construct() {
 parent::__construct();
 $this->load->helper('url');
$this->load->library('m_pdf');
 $this->load->model('boq_pdf_model');
 $this->load->model('project_list_model');
}
function pdf()
{
 $id= $this->uri->segment(3) ; 
 $data['projects'] = $this->project_list_model->show_projects();
$data['boq'] = $this->boq_pdf_model->get_boq($id);
 $this->load->view('boq/boq_report',$data);

}
public function topdf(){
//this data will be passed on to the view
$data['the_content']='RCJ Constructions';

//load the view, pass the variable and do not show it but "save" the output into $html variable
$html=$this->load->view('boq/boq_report', $data, true); 

//this the the PDF filename that user will get to download
$pdfFilePath = "boq_report.pdf";

//load mPDF library
//$this->load->library('m_pdf');
//actually, you can pass mPDF parameter on this load() function
$pdf = $this->m_pdf->load();


$id= $this->uri->segment(3) ; 
$data['projects'] = $this->project_list_model->show_projects();
$data['boq'] = $this->boq_pdf_model->get_boq($id);
$html = $this->load->view('boq/boq_report', $data, true);

//generate the PDF!
$pdf->WriteHTML($html);


//offer it to user via browser download! (The PDF won't be saved on your server HDD)
$pdf->Output($pdfFilePath, "D");
    }
}
?>

模型文件

function get_boq($id){ 
    $this->db->select('*');
        $this->db->from('boq');
        $this->db->join('project', 'project.id = boq.project_id'); 
        $this->db->where('project.id',$id);
        $this->db->order_by('item_no','ASC');
        $getData = $this->db->get();
        if($getData->num_rows() > 0)
        return $getData->result_array();
        else return null; 

    }
}

查看文件

 <?php
     foreach ($boq as $rows) {
       <tr>
          <td><?php echo $rows['unit'] ?></td>
          <td><?php echo $rows['rate']?></td>
          <td><?php echo $rows['laboure_hrs'] ?></td>
          <td><?php echo $rows['laboure_cost'] ?></td>
       </tr>
   <?php
       //$i++;
       }
   ?>

采购 list

编号 |率|单位|项目编号

项目表

编号 |地点| client_id

For your information, i am using MPDF library as well and i am loading it in my controller.

任何帮助将不胜感激？

谢谢

Answer 1

您必须检查值是否存在。如果模型返回 null 意味着它将显示错误 invalid argument。所以，这样做:-

<?php
if(count($boq) > 0) { 
    foreach ($boq as $rows) {
        <tr>
           <td><?php echo $rows['unit'] ?></td>
           <td><?php echo $rows['rate']?></td>
           <td><?php echo $rows['laboure_hrs'] ?></td>
           <td><?php echo $rows['laboure_cost'] ?></td>
        </tr>
<?php
       //$i++;
    }
} else {
    echo "No Results Found";
}
?>