如何从React Native中的数组访问多个JSON响应?

Usually, I would access the response of the JSON by using reponseJson in React Native, but how would I access more than one response?

I have it json_encoded here from php:

Login.php

if ($row = mysqli_fetch_array($result)) {
     $allresults = array( 'Data Matched' => $objA, "Hello" => $objB );
        $Success = 'Data Matched';
     // Converting the message into JSON format.
    $Success = json_encode($allresults);

    // Echo the message.
     echo $Success ; 
} else {}

When I try to access it by responseJson.objA, I get this error: [object Object] in React Native:

    Login = () =>{
this.setState({ loading: true, disabled: true }, () =>{

fetch('http://www.exmaple.com/React/login.php', {
 method: 'POST',
 headers: {
   'Accept': 'application/json',
   'Content-Type': 'application/json',
 },
 body: JSON.stringify({

   username: username,

 })

}).then((response) => response.json())
     .then((responseJson) => {

       // If server response message same as Data Matched
      if(responseJson.objA === 'Data Matched')**<-- Want the first response to go here** 
       {
            this.dropdown.alertWithType('success', 'Login Success', reponseJson.objB); **<-- Want the second response to go here**
        }
       }).catch((error) => {
      console.log(error);
     });

I followed this question from SO, what am I doing wrong? multiple JSON object response

You may want to put this code before the if statement in your react native code,

alert(JSON.stringify(responseJson, null, 1));

so you can see the response in string form.