您的C＃类映射不使用JSON结构相匹配。

Your c# class mapping doesn't match with json structure.

解决方案：

class MovieCollection {
        public IEnumerable<Movie> movies { get; set; }
}

class Movie {
        public string title { get; set; }
}

class Program {
        static void Main(string[] args)
        {
                string jsonString = @"{""movies"":[{""id"":""1"",""title"":""Sherlock""},{""id"":""2"",""title"":""The Matrix""}]}";
                JavaScriptSerializer serializer = new JavaScriptSerializer();
                MovieCollection collection = serializer.Deserialize<MovieCollection>(jsonString);
        }
}