Question

我有一些$competitors（这是从MySQL检索的对象数组）（比如9），我有$competitors[i]->minSingleCarefee数据，即费用数据。我想平均这个费用数据，但可能是数据集不完整，即我没有所有9个竞争对手的费用数据。因此，我通过使用if语句跟踪它，如果费用数据可用，则递增$data_available。

我的问题是，似乎代码存在缺陷，因为它只返回第一个竞争对手的费用价值......我不明白为什么！当我回应时，$ data_available总是最终为0.

//declaring variables
$mm_avg_fees = 0;
$data_available = 0;

//function to calculate average fees
function avg_fees($competitors, $mm_avg_fees, $data_available){

        foreach ($competitors as $competitor) {
            //impose condition to increment data_available
            //only if there is data in the minSingleCareFee column for the $competitor
            if ($competitor->minSingleCareFee != NULL) {
                $mm_avg_fees = $mm_avg_fees + $competitor->minSingleCareFee;
                $data_available = $data_available + 1; 
            } else {}
        }
    return $mm_avg_fees / $data_available;
}

echo echo 'The current average for single room fees in your micromarket is: ' . avg_fees($competitors, $mm_avg_fees, $data_available);

Answer 1

是否在课堂内？如果确实如此，你不能这样做。
其他{}是不必要的。
你可以做$ data_available ++而不是那里有什么。
您正在将var视为对象。它是什么，变量或对象？

$ competitor-＆GT; minSingleCareFee

并且你已经确定竞争对手是当时竞争对手阵容的价值。

Answer 2

使用此：

//declaring variables
$mm_avg_fees = 0;
$data_available = 0;

//function to calculate average fees
function avg_fees($competitors, $mm_avg_fees, $data_available){

        foreach ($competitors as $competitor) {
            //impose condition to increment data_available
            //only if there is data in the minSingleCareFee column for the $competitor
            if (!empty($competitor->minSingleCareFee)) {
                $mm_avg_fees = $mm_avg_fees + $competitor->minSingleCareFee;
                $data_available = $data_available + 1; 
            }
        }
    return $mm_avg_fees / $data_available;
}

echo 'The current average for single room fees in your micromarket is: ' . avg_fees($competitors, $mm_avg_fees, $data_available);

php中的foreach和loop语句问题

2 个答案: