如何使用php获取foreach循环中多维数组的键？

Question

我需要为给定主题打印以下数组中的学生姓名和标记：

$marks = [
    "john" => ["physics" => 30, "maths" => 55, "chemistry" => 66],
    "jack" => ["physics" => 44, "maths" => 19, "chemistry" => 87],
    "mark" => ["physics" => 77, "maths" => 66, "chemistry" => 67],
];

我理解，如果我echo $marks['john']['chemistry'];它会打印出学生/科目的标记，但我应该如何接近 foreach 循环来显示所有学生及其化学成绩？

Answer 1

在php foreach()中，您可以获得当前项目的密钥

foreach ($array as $key=>$item){...}

也像底码

一样使用它

foreach ($marks as $name=>$scores){
    echo $name .":". $scores["chemistry"];
}

查看demo

中的代码结果