get the value from JSON String(SOAP content)

[Kumar Ponmaheswaran]

I have a JSON String which will contain SOAP Message content. This is my JSON string:

{
   "xml":{

   },
   "SOAP-ENV:Envelope":{
      "@attributes":"....."
   },
   "SOAP-ENV:Body":{
      "@attributes":{
         "billVo":{
            "customerDetail":{
               "customerFirstName":{
                  "#text":"Mahes"
               }
            }
         }
      }
   }
}

I want to get the value of customerFirstName.
Give me some suggestions how to get it.
Thanks