PHP循环+二维数组

Question

我正在尝试使用PHP创建一个二维数组，但仍然没有弄清楚。

$value = 3;
$sql = "SELECT country, capital  FROM world WHERE client = 2 ";
$myArray = array();
try {
    foreach ($connection->query($sql) as $row)
    {
        for($i=0; $i<$value; $i++){
            $myArray[$i] = array($row['country'], $row['capital']);
        }
    }
}

我尝试了函数"array_push"，但它不是获得特定值的最佳方式。

Answer 1

您正在对查询的单个结果进行循环。for()循环是完全不必要的:

$myArray = array();
foreach ($connection->query($sql) as $row)
    $myArray[] = array($row['country'], $row['capital']);
}

Answer 2

你不应该需要for循环:

$sql = "SELECT country, capital  FROM world WHERE client = 2 ";
$myArray = array();
foreach ($connection->query($sql) as $row) {
   $myArray[] = array("country" => $row['country'], "capital" => $row['capital']);    
}

Answer 3

您不需要for循环，并且由于您在查询中指定列，因此只需为关联数组执行此操作:

foreach ($connection->query($sql, PDO::FETCH_ASSOC) as $row)
    $myArray[] = $row;
}

或者如果你想要数字索引，那么:

$connection->query($sql, PDO::FETCH_NUM)

或者您想访问$myArray['England']之类的东西并获得London ?然后像这样构建数组:

foreach ($connection->query($sql, PDO::FETCH_ASSOC) as $row)
    $myArray[$row['country']] = $row['capital'];
}