json_encode()不返回json数组

Question

我试图在php中编码一个关联数组。

$data = array(
        "firstName" => $_POST["firstName"],
        "lastName" => $_POST["lastName"],
        "email" => $_POST["email"],
        "telephone" => $_POST["telephone"]
);

但是，输出是字符串格式，而不是数组格式。

string(98) "{"firstName":"rob","lastName":"shelford","email":"some@domain.co.uk","telephone":"01245454545"}"

输出需要有方括号，以便接收服务器能够正确地读取数据。

对于我需要使用的$data数组，还有其他语法吗？

编辑1

官方的PHP文档https://www.php.net/manual/en/function.json-encode.php

国家

echo "Normal: ",  json_encode($a), "\n";

可用于输出

Normal: ["<foo>","'bar'","\"baz\"","&blong&","\u00e9"]

然而，当我尝试使用"\n"标志时，我会收到一个错误

编辑2

我希望转换的全部数据

$data = array(
        "applicants" => array(
          "firstName" => $_POST["firstName"],
          "lastName" => $_POST["lastName"],
          "email" => $_POST["email"],
          "telephone" => $_POST["telephone"]
        ),
    "buyerType" => $_POST["buyerType"],
    "organisationId" => "xxxxxxxxxx",
    "introducerId" => "0",
    "introducerBranchId" => "0",
    "introducerNegotiatorId" => "0",
);

编辑3是通过将它传递到json_encode()中来实现的：

$data = array(

  "applicants"=> [
    array(
      "email"=> $_POST["email"],
      "firstName"=> $_POST["firstName"],
      "lastName"=> $_POST["lastName"],
      "telephone"=> $_POST["telephone"]
    )
  ],
  "buyerType" => $_POST["buyerType"],
  "organisationId" => "xxxxxxxxxx",
);

我还删除了上面示例中不必要的行。

编辑4

在实现EDIT3之后，我期望并实际得到的实际输出

string(138) "{"applicants":[{"email":"some@domain.co.uk","firstName":"rob","lastName":"test","telephone":"01200000000"}],"buyerType":"Purchase"}"

Answer 1

如果希望嵌套数组被方括号包围，只需将其放在php中的数组中即可。

$data['applicants'] = [$data['applicants']];
echo json_encode($data);

FYI索引数组[1,2]将被编码到json列表[1,2]，关联数组['x'=>1,'y'=>2]将被编码到json对象{"x":1,"y":1}。