如何解决php csv乱码问题

/**
 * 重写fputcsv方法，添加转码功能
 * @param $handle
 * @param array $fields
 * @param string $delimiter
 * @param string $enclosure
 * @param string $escape_char
 */
function fputcsv2($handle, array $fields, $delimiter = ",", $enclosure = '"', $escape_char = "\\") {
    foreach ($fields as $k => $v) {
        $fields[$k] = iconv("UTF-8", "GB2312//IGNORE", $v);  // 这里将UTF-8转为GB2312编码
    }
    fputcsv($handle, $fields, $delimiter, $enclosure, $escape_char);
}

function test () {
    // 文件名
    $filename = "订单查询结果" . date('Y-m-d H:i:s');
 
    // 设置输出头部信息
    header('Content-Encoding: UTF-8');
    header("Content-Type: text/csv; charset=UTF-8");
    header("Content-Disposition: attachment; filename={$filename}.csv");
 
 
    $tableHead = array('#', '订单id', '订单号', '分类', '客户信息', '工匠信息', '订单状态', '施工状态', '付款状态', '订单金额', '下单时间', '备注');
 
    // 获取句柄
    $output = fopen('php://output', 'w') or die("can't open php://output");
 
    // 输出头部标题
    fputcsv2($output, $tableHead);
 
    $list = array();
    foreach ($list as $item) {
        fputcsv2($output, array_values($item));
    }
 
    // 关闭句柄
    fclose($output) or die("can't close php://output");
}