php for loop in a foreach loop, 不知道该怎么做

Question

我正在尝试在 foreach 循环中执行 for 循环。

我的数据库中有一个 table 如下：

ID        | Fname | Lname
------------------------
1          Bart    Simpson
1          Mickey  Mouse
2          Peter   Griffin
2          Clark   Kenet
2          David   Johnson

我从数据库中调用数据（它可以工作，在 phpmyadmin 上测试过），我希望数据以 ID 值显示在页面上，例如：

巴特·辛普森、米老鼠和彼得·格里芬

克拉克·肯尼特和大卫·约翰逊

正如您在任何行的姓氏前看到的“&”，但这不是我的问题。

这是我写的代码：

//HERE I RETRIVE ALL THE DATA FROM THE DATABASE.
$query = $dbh->query(" SELECT *
        FROM table
        WHERE ID= '{$ID}'
        ");   

//THIS CODE SHOWS THE NUMBER OF ROWS WITH THE CURRENT ID 
        $sql    = "SELECT COUNT( * ) FROM table WHERE ID= '{$ID}'";
        $result = $dbh->prepare($sql);
        $result->execute();
        $number_of_rows = $result->fetchColumn();

//THIS IS THE FOREACH IN WHICH I CALL ALL THE ROWS BY THEIR VALUE
          foreach ($query as  $key =>$value) {
                   $value['wFname'][$key] = !empty($value['wFname'][$key]) ? $value['wFname'][$key] : '';                      
$numRow = $number_of_rows-2; // THE ITEM BEFORE THE LAST ONE IN THE ARRAY
$lastItem = $number_of_rows-1; //LAST INDEX IN THE ARRAY
for($counter = 0; $counter = $numRow; $counter++){
 return  $value['wLname'][$counter] . ', '.  $value['wFname'][$counter];
  }
   return  "&" . $value['wLname'][$lastItem] . ', '.$value['wFname'][$lastItem] ;
   return ' ';

                };

使用此代码，我只得到每个 ID 的第一对名称。任何帮助都会很棒。

Answer 1

尝试更改：

for($counter = 0; $counter = $numRow; $counter++){

至：

for($counter = 0; $counter =< $numRow; $counter++){

您正在检查 $counter 是否等于 $numRow，您应该检查它是否等于且小于...

希望对您有所帮助。

根据用户请求编辑

尝试将结果存储在一个变量中，并在两个循环结束时 return 该变量，但我不确定您要在这里实现什么，请尝试运行以下代码：

//HERE I RETRIVE ALL THE DATA FROM THE DATABASE.
        $query = $dbh->query(" SELECT *
        FROM table
        WHERE ID= '{$ID}'
        ");

//THIS CODE SHOWS THE NUMBER OF ROWS WITH THE CURRENT ID 
        $sql = "SELECT COUNT( * ) FROM table WHERE ID= '{$ID}'";
        $result = $dbh->prepare($sql);
        $result->execute();
        $number_of_rows = $result->fetchColumn();

//THIS IS THE FOREACH IN WHICH I CALL ALL THE ROWS BY THEIR VALUE
        $return = "";
        foreach ($query as $key => $value) {
            $value['wFname'][$key] = !empty($value['wFname'][$key]) ? $value['wFname'][$key] : '';
            $numRow = $number_of_rows - 2; // THE ITEM BEFORE THE LAST ONE IN THE ARRAY
            $lastItem = $number_of_rows - 1; //LAST INDEX IN THE ARRAY
            for ($counter = 0; $counter <= $numRow; $counter++) {
                $return .= $value['wLname'][$counter] . ', ' . $value['wFname'][$counter];
            }
            $return .= "&" . $value['wLname'][$lastItem] . ', ' . $value['wFname'][$lastItem];
            $return .= ' ';
        }
        return $return;

php for loop in a foreach loop, 不知道该怎么做

php for loop inside a foreach loop, not sure how to do it

php

foreach

for-loop

根据用户请求编辑