从mysqli准备好的语句中获取单行数据 [英] Fetch a single row of data from mysqli prepared statement

问题描述

我有以下代码，如果找到 1 行，我想将结果设置为 $aPrds，我该怎么做?

I have the following code and where if 1 row is found I would like to set the result to $aPrds, how can I do this?

$stmt = $db->prepare("select * from products where id=?");
$stmt->bind_param("s", $_GET['id']);

if($stmt->execute())
{
  $stmt->store_result();
  echo $stmt->num_rows;
  if($stmt->num_rows==1)
  {
    //SET RETURNED ROW TO aPrds 

  }
  else
  {
    echo "no results or too many found";
  }
}
else
{
   echo "sql invalid";
}

我也尝试了以下代码，但不成功(返回(空):

I have also tried the following code which has been unsuccessful (returns (null):

$stmt = $db->prepare("select productid, product_name, description from product where productid=?");
$a=1;
$stmt->bind_param("i", $a);
if($stmt->execute()){
    $stmt->store_result();
    if($stmt->num_rows==1){
        $stmt->bind_result($b, $c, $d);         
        print_r($b);
        print_r($c);
        print_r($aPrds);
    }else{
        echo "no result or more than 1 returned";
    }
}else{
    echo "invalid sql";
}

请注意，我已经测试了 SQL 并且它有效，而且 $db mysqli 连接也肯定有效.

Please note that I have tested the SQL and it works, also the $db mysqli connection is definitely working.

推荐答案

我认为您正在寻找 get_result 和 fetch_assoc 方法:

I think you are looking for the get_result and fetch_assoc methods:

// ....
$result = $stmt->get_result();
$aPrds = $result->fetch_assoc();
// ....

显然这些功能尚不可用(应该已经测试过了，抱歉).所以这是经过测试的:

Apparently these functions are not yet available (should have tested this, sorry). So this is tested:

function bind_array($stmt, &$row) {
    $md = $stmt->result_metadata();
    $params = array();
    while($field = $md->fetch_field()) {
        $params[] = &$row[$field->name];
    }

    call_user_func_array(array($stmt, 'bind_result'), $params);
}

// ....

if($stmt->execute()) {
    bind_array($stmt, $row);
    $stmt->fetch();

    print_r($row);

    // ....

如果您在 $stmt->bind_result($b, $c, $d); 之后添加了 $stmt->fetch() ，那么您的第二个解决方案也应该有效；

And you second solution should also work if you added $stmt->fetch() after $stmt->bind_result($b, $c, $d);

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