php - 如何在 foreach 循环中打印一个值？

Question

$id = 123;

$my_var[$id]["lname"] = "Smith";
$my_var[$id]["fname"] = "John";

foreach ($my_var as $rec) {
    print "Last Name: " . $rec["lname"]. "\n";
    print "First Name: " . $rec["fname"]. "\n";

    // print "ID: " . $id . "\n";      // THIS WORKS BUT NOT WHAT I WANT
    print "ID: " . $rec[$id] . "\n";     // DOESNOT WORK
}

如何在不直接使用 $id 的情况下在 foreach() 循环中打印 $id 的值？

Answer 1

foreach在循环中指定键和值。我在$key这里调用它，因为您已经使用了$id，但您不妨回收该名称。

foreach ($my_var as $key => $rec)
{
   print "Last Name: " . $rec["lname"]. "\n";
   print "First Name: " . $rec["fname"]. "\n";

   print "ID: " . $key . "\n";   
}

Answer 2

在 PHP 中，您可以按照以下方式访问关联数组中的键：

$id = 123;

$my_var[$id]["lname"] = "Smith";
$my_var[$id]["fname"] = "John";

foreach ($my_var as $key => $rec) {
    print "Last Name: " . $rec["lname"]. "\n";
    print "First Name: " . $rec["fname"]. "\n";

    print "ID: " . $key . "\n";     // Is your ID
}