您的原始json字符串(在aKzenT进行编辑之前)被两次转义，我使用var str2 = Regex.Unescape(str);来获取实际的字符串.

Your original json string(before aKzenT's edit) was double escaped and I used var str2 = Regex.Unescape(str); to get the actual string .

public class RawAnswer
{
     public string id { get; set; }
     public string ans { get; set; }

}

并且不需要AnswerList

现在您的代码可以工作了

Now your code can work

JavaScriptSerializer serializer = new JavaScriptSerializer();
List<RawAnswer> ListAnswers = serializer.Deserialize<List<RawAnswer>>(str);