将IList<T>泛型转换成Json

    private string SwitchToJson<T>(IList<T> li) where T : class
    {
        if (li.Count <= 0)
            return "";

        Type tp = typeof(T);
        BindingFlags bf = BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Static;//反射标识
      PropertyInfo[] proInfo = tp.GetProperties(bf);//获取T的属性

      StringBuilder sb = new StringBuilder();
        StringWriter sw = new StringWriter(sb);
        using (JsonWriter jsonWriter = new JsonTextWriter(sw))
        {
            jsonWriter.Formatting = Formatting.Indented;
            foreach (PropertyInfo info in proInfo)//遍历对象属性
            {
                jsonWriter.WriteStartObject();
                jsonWriter.WritePropertyName(info.Name);
                jsonWriter.WriteStartArray();
                foreach (T item in li)//遍历每个对象
                {
                    object value = info.GetValue(item, null);//通过属性获取当前对象的属性值
                    jsonWriter.WriteValue(value.ToString());
                }
                jsonWriter.WriteEndArray();
                jsonWriter.WriteEndObject();
            }
        }
        sw.Close();
        return sb.ToString();
    }