将所有响应放在范围内的问题

Question

$latN = $_POST["latN"];
$latS = $_POST["latS"];
$longE = $_POST["longE"];
$longW = $_POST["longW"];

$statement = mysqli_prepare($con, "SELECT * FROM find WHERE lat <= latN AND lat >= latS
AND lng >= longW AND lng <= longE");
mysqli_stmt_bind_param($statement, "ss", $lat, $long);
mysqli_stmt_execute($statement);

mysqli_stmt_store_result($statement);
mysqli_stmt_bind_result($statement, $lat, $long);

$response = array();
$response["success"] = false;

while(mysqli_stmt_fetch($statement)){
    $response["success"] = true;
    $response["lat"] = $lat;
    $response["long"] = $long;
}

print_r(json_encode($response));

我通过android以字符串的形式将latN，latS，longE，longW发布到此页面，我试图找出我所拥有的值范围内是否有任何坐标给出。我很难过，无法解决为什么这一切都是假的。有什么想法吗？