有没有办法检查对象中的值是否设置为不使用foreach？

Question

I have the following JSON object:

{
  "screen": 1,
  "parameters": {
    "title": "Fill in the form:",
    "values": [
      {
        "id": 13,
        "type": 2,
        "name": "A",
        "label": "Lorem ipsum",
        "value": 10
      },
      {
        "id": 14,
        "type": 2,
        "name": "B",
        "label": "Lorem ipsum",
        "value": 20
      }
    ]
  }
}

In the code I access the values using $screen = /*object*/; $screen->parameters->values.

Is there a fast way to check if the values of answer A and B are filled in? I tought something like this:

if(isset(A) && isset(B)) { ... }

For those who are interested, I use laravel 5, maybe there is a method for it?

It looks like I need an foreach, but I rather avoid those in this case...

Answer 1

Nope, not with the current structure. You could however change the structure a bit to support this. You could use an object instead of an array and use the name as keys:

{
  "screen": 1,
  "parameters": {
    "title": "Fill in the form:",
    "values": {
      "A":{
        "id": 13,
        "type": 2,
        "label": "Lorem ipsum",
        "value": 10
      },
      "B":{
        "id": 14,
        "type": 2,
        "label": "Lorem ipsum",
        "value": 20
      }
    ]
  }
}

You could then use your isset method.

isset( $screen->parameters->values->A );

You can still loop over the values as you can turn this whole thing in an associative array by passing true to json_decode as a second parameter. I for one am not a big fan of my own answer, and would probably just loop the thing, but it may still answer your question.

edit: I forgot that if you add true to json_decode, you also access your properties like this:

isset( $screen['parameters']['values']['A'] );