看不懂的php数据结构？

Question

这是我拿到的一组php数据，我突然看不明白这是什么数据了？我去遍历不行，用arr[0]可以拿到objectclass的数组，但是这数组为什么是(6)?

array(6) {
  ["count"] => int(5)
  [0] => array(8) {
    ["objectclass"] => array(3) {
      ["count"] => int(2)
      [0] => string(3) "top"
      [1] => string(18) "organizationalUnit"
    }
    [0] => string(11) "objectclass"
    ["ou"] => array(2) {
      ["count"] => int(1)
      [0] => string(6) "people"
    }
    [1] => string(2) "ou"
    ["description"] => array(2) {
      ["count"] => int(1)
      [0] => string(18) "存放人员信息"
    }
    [2] => string(11) "description"
    ["count"] => int(3)
    ["dn"] => string(38) "ou=people,dc=info,dc=huel,dc=edu,dc=cn"
  }
  [1] => array(8) {
    ["objectclass"] => array(3) {
      ["count"] => int(2)
      [0] => string(3) "top"
      [1] => string(18) "organizationalUnit"
    }
    [0] => string(11) "objectclass"
    ["ou"] => array(2) {
      ["count"] => int(1)
      [0] => string(5) "admin"
    }
    [1] => string(2) "ou"
    ["description"] => array(2) {
      ["count"] => int(1)
      [0] => string(27) "存放管理员用户信息"
    }
    [2] => string(11) "description"
    ["count"] => int(3)
    ["dn"] => string(47) "ou=admin,ou=people,dc=info,dc=huel,dc=edu,dc=cn"
  }
  [2] => array(8) {
    ["objectclass"] => array(3) {
      ["count"] => int(2)
      [0] => string(3) "top"
      [1] => string(18) "organizationalUnit"
    }
    [0] => string(11) "objectclass"
    ["ou"] => array(2) {
      ["count"] => int(1)
      [0] => string(4) "adm2"
    }
    [1] => string(2) "ou"
    ["description"] => array(2) {
      ["count"] => int(1)
      [0] => string(30) "存放重置密码用户信息"
    }
    [2] => string(11) "description"
    ["count"] => int(3)
    ["dn"] => string(46) "ou=adm2,ou=people,dc=info,dc=huel,dc=edu,dc=cn"
  }
  [3] => array(8) {
    ["objectclass"] => array(3) {
      ["count"] => int(2)
      [0] => string(3) "top"
      [1] => string(18) "organizationalUnit"
    }
    [0] => string(11) "objectclass"
    ["ou"] => array(2) {
      ["count"] => int(1)
      [0] => string(7) "teacher"
    }
    [1] => string(2) "ou"
    ["description"] => array(2) {
      ["count"] => int(1)
      [0] => string(24) "存放教师用户信息"
    }
    [2] => string(11) "description"
    ["count"] => int(3)
    ["dn"] => string(49) "ou=teacher,ou=people,dc=info,dc=huel,dc=edu,dc=cn"
  }
  [4] => array(8) {
    ["objectclass"] => array(3) {
      ["count"] => int(2)
      [0] => string(3) "top"
      [1] => string(18) "organizationalUnit"
    }
    [0] => string(11) "objectclass"
    ["ou"] => array(2) {
      ["count"] => int(1)
      [0] => string(7) "student"
    }
    [1] => string(2) "ou"
    ["description"] => array(2) {
      ["count"] => int(1)
      [0] => string(24) "存放学生用户信息"
    }
    [2] => string(11) "description"
    ["count"] => int(3)
    ["dn"] => string(49) "ou=student,ou=people,dc=info,dc=huel,dc=edu,dc=cn"
  }
}

Answer 1

0、1、2、3、4、"count"，这不正好 6 个元素么……

$data = array(
  "count" => 5,
  array(), // 里面的内容懒得打了
  array(),
  array(),
  array(),
  array()
);
var_dump($data);

你要是 foreach 遍历不了，那可能它是个自定义的 class 实例，重写了 Iterable。具体是啥类型你就 get_class 打印看看呗。