Question

我正在运行for循环来从论坛表中收集数据，但是如果没有返回结果，我不太清楚如何处理它。这是我必须收集数据的代码。

$q = $this->db->query("SELECT * FROM newslist ORDER BY pubdate DESC");
if ($q->num_rows() > 0) {
    foreach ($q->result() as $row) {
        $data[] = $row;
    }
}
return $data; else {
    return echo = "nose";
}

Answer 1

$q = $this->db->query("SELECT * FROM newslist ORDER BY pubdate DESC");
$data = array(); // Initialize the array in case there are no records.
if ($q->num_rows() > 0){
  foreach ($q->result() as $row){
    $data[] = $row;
  }
}
if (empty($data)) { // If there are no records, $data will be empty.
  return "nose";
}
else { // If $data has records, will return data from SQL.
  return $data;
}

<强>解释

1）初始化$data变量。如果我们没有得到任何记录，则不会追加$data，导致初始化变量$data返回错误。通过在循环之前初始化它，我们正在克服它。

2）检查empty()的{{1}}，如果为空，则返回错误字符串，否则为$data。

Answer 2

流量问题的一点点。见修订后的解决方案。

$q = $this->db->query("SELECT * FROM newslist ORDER BY pubdate DESC");
        if($q->num_rows() > 0){
            foreach($q->result() as $row){
                $data[] = $row;
            }

            return $data;
        } //<-- this was on the wrong line
        else {
            return "No data!";
        }

Answer 3

在if条件下返回您的数据，不要同时使用return and echo。

$q = $this->db->query("SELECT * FROM newslist ORDER BY pubdate DESC");
if ($q->num_rows() > 0) {
    foreach ($q->result() as $row) {
        $data[] = $row;
    }
    return $data;// return data inside if condition
}
 else {
    return "nose";// remove echo from here
}

Answer 4

只需您可以使用此

$query = $this->db->query("SELECT * FROM newslist ORDER BY pubdate DESC");
$result = $query->result_array();
$count = count($result);// counting data 

if(empty($count))
{
    $log = 'nose';
    return $log;
}
else
{
    return $result;
}

如何处理php forloop返回没有结果

4 个答案: