问将存储在JSON数组中的字符串转换为PHP中的变量名

EN

 //Have not put the complete json file. No error in the file
 {
 "loginType":[
    {
        "name":"Facebook",
        "url":"#",
        "method":"",
        "label":"Continue with Facebook",
        "type":"social",
        "class":"",
        "icon":"",
        "callBack_url" : "fbLoginUrl",
        "providerButton":"<div class='fb-login-button' data-max-rows='1' 
        data-size='large' data-button-type='continue_with' data-use- 
        continue-as='true'></div>"        
    },
    {
        "name":"Twitter",
        "url":"#",
        "method":"logInWithTwitter()",
        "label":"Continue with Twitter",
        "type":"social",
        "class":"",
        "icon":"",
        "callBack_url" : "twitterLoginUrl",
        "providerButton" :""
      }
    ]
}

$jsonData_signIn =json_decode
(file_get_contents(/path/to/oauth2_provider.json)); 
 $oauth2Provider = jsonData_signIn->loginType;
       foreach($oauth2Provider as $type){
         if($type->type == 'local' ){
           echo "<a href=\"{$type->callBack_url}\">{$type->label}</a>";
         }
    }    

echo "<a href=\"{${$type->callBack_url}}\">{$type->label}</a>";