CodeIgniter :模型变量中未定义的索引

Question

我的模型中有以下代码。我正在加载报价详细信息页面，它给了我错误

Severity: Notice
Message: Undefined index: viewc
Filename: statistics/Statistic_model.php
Line Number: 551

Statistic_model：

public function getTotalDetailsViewOfActiveOffer($comid) {
$this->db->select('count(statistic_offer_view_count.id) as viewc');
$this->db->from('statistic_offer_view_count');
$this->db->join('offers', 'offers.id = statistic_offer_view_count.offer_id');       
$this->db->where('offers.com_id',$comid);
$this->db->where('offers.approved_status',"2"); 
$this->db->where('offers.enddate >=',date('Y-m-d'));
$this->db->group_by("offers.com_id");       
$query = $this->db->get();
$row = $query->result_array();
$count=$row['viewc'];           //this is line 551
}

知道如何解决此错误吗？

Answer 1

该错误意味着索引viewc不在数组中$query->result_array()很可能是因为查询失败或返回 null。你应该养成做以下事情的习惯：

$query = $this->db->get();
if ($query->num_rows() > 0) {
return $query->row()->viewc;
}
return false; // or in this case 0 or whatever

Answer 2

在你的代码中，你从数据库中选择数据 多个数组。并像单个数组一样将 at 分配给变量。 你的代码....

$row = $query->result_array();
$count=$row['viewc'];

正确的方法是在你的传导中分配一个变量是....

$data   =   array();
foreah($row as $key => $value){
$data[$key] = $value['viewc'];
}