// MARK:字符串转字典
func stringValueDic(_ str: String) -> [String : Any]?{
let data = str.data(using: String.Encoding.utf8)
if let dict = try? JSONSerialization.jsonObject(with: data!, options: JSONSerialization.ReadingOptions.mutableContainers) as? [String : Any] {
return dict
}
return nil
}