php中foreach和loop语句的问题

我有许多

$competitors

（这是从MySQL检索到的一个对象数组）（比如9），我有

$competitors[I]->minSingleCarefee

数据，即费用数据。我想对这些费用数据进行平均，但可能是数据集不完整，即我没有9个竞争对手的所有费用数据。因此，我通过使用if语句并在费用数据可用时递增

$data\u available

来跟踪这一点

我的问题是，代码似乎有缺陷，因为它只返回第一个竞争对手的费用值。。。我不知道为什么！另外，当我回显$data_时，它总是以0结尾

//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);

是在教室里吗？如果是这样，你就不能那样做

else{}是不必要的

您可以使用$data_available++代替现有的功能

您将变量视为对象。它是什么，变量还是对象

$competitor->minSingleCareFee

您已将competitor设置为此时competitors数组的值。

使用以下方法：

//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);

---

请发布var_转储（$competitors）；尝试将此

if（$competitor->minSingleCareFee！=NULL）{

更改为此

if（！is_NULL（$competitor->minSingleCareFee））{

在我们知道$competitors内部的内容之前帮不上忙。因此按照@user574632@user574632这里是一个数据转储块：数组（5）{[0]=>object（stdClass）#153（41）{[“id”]=>字符串（1）“1”[“PostcodeinCodepointFormat”]=>字符串（6）“XXXXX”[“Home_name”]=>字符串（9）“XXXXXX”[“minSingleCareFee”]字符串（3）“750”@sankalphatt这是数据转储：数组（5）{[0]=>对象（stdClass）{153（41）{[“id”=>字符串（1）“1”[“Postcodeincodeincodepointormat”]=>字符串（6）“XXXXX”[“Home_name”]=>字符串（9）“XXXXXX”[]字符串（3）“750”等…更多关于提示而非答案。好的，让我检查一下…是否有一种方法可以让我访问avg_费用函数之外的$data_可用变量？使用全局关键字。参考：