Newtonsoft JSON 不包含 'Item' 的定义

Question

我试图从Json数组中获得Json对象在我的web服务项目…我得到这个错误:

Newtonsoft JSON does not contain definition for 'Item' ,

我还尝试使用其他函数来代替"Item"函数，但这不起作用

顺便说一下，我使用了一个VB到c#的在线转换工具来生成这个代码…

这是我的代码

 try
        {
            HttpContext context = this.Context;
            string strJson = "";
            JArray OrderItems = JArray.Parse(JSONString);
            //Dim IncrementalConnection As New SqlConnection()
            SqlConnection conn = new SqlConnection(connectionString);
            conn.Open();
            SqlCommand IncrementalIdCommand = new SqlCommand("INSERT INTO TheOrderIds DEFAULT VALUES; SET @AutoID=SCOPE_IDENTITY()", conn);
            SqlParameter Param = new SqlParameter();
            Param.ParameterName = "@AutoID";
            Param.Size = 4;
            Param.Direction = ParameterDirection.Output;
            IncrementalIdCommand.Parameters.Add(Param);
            IncrementalIdCommand.ExecuteNonQuery();
            int OrderId = Convert.ToInt32(Param.Value);
            conn.Close();
            foreach (JObject OrderItem in OrderItems)
            {
                string strSQL = "insert into Orders(ProductNumber,Name,Category,Price,OrderId,TableNumber,WaiterName,CashierName,DateAndTime,isActive,isCoocked,isPaid,isYesCanceled,ProductQuantity,extraQty,PaidDate,isDiscounted, DicountPercent, AfterDiscount) values(@x,@y,@a,@b,@c,@d,@e,@f,@g,@h,@i,@j,@k,@l,0,getDate(),0,0,0)";
                conn.Open();
                SqlCommand cmd = new SqlCommand(strSQL, conn);
                cmd.Parameters.AddWithValue("@x", OrderItem.Item("ProductNumber").ToString());
                cmd.Parameters.AddWithValue("@y", OrderItem.Item("Name").ToString());
                cmd.Parameters.AddWithValue("@a", OrderItem.Item("Category").ToString());
                cmd.Parameters.AddWithValue("@b", OrderItem.Item("Price").ToString());
                cmd.Parameters.AddWithValue("@c", OrderId);
                cmd.Parameters.AddWithValue("@d", OrderItem.Item("TableNumber").ToString());
                cmd.Parameters.AddWithValue("@e", OrderItem.Item("WaiterName").ToString());
                cmd.Parameters.AddWithValue("@f", OrderItem.Item("CashierName").ToString());
                cmd.Parameters.AddWithValue("@g", OrderItem.Item("DateAndTime").ToString());
                cmd.Parameters.AddWithValue("@h", OrderItem.Item("isActive").ToString());
                cmd.Parameters.AddWithValue("@i", OrderItem.Item("isCoocked").ToString());
                cmd.Parameters.AddWithValue("@j", OrderItem.Item("isPaid").ToString());
                cmd.Parameters.AddWithValue("@k", OrderItem.Item("isYesCanceled").ToString());
                cmd.Parameters.AddWithValue("@l", OrderItem.Item("ProductQuantity").ToString());
                cmd.ExecuteNonQuery();
                conn.Close();
            }
            //ProductNumber As [String], Name As [String], Category As [String], Price As [String], OrderId As [String]'
            //this is the bridge to database
            string json = "{"result":"1", "exception":" + "" + """ + "NULL" + """ + ""}";
            context.Response.Write(strJson);
        }
        catch (Exception ex)
        {
            string json = "{"result":"0", "exception":" + "" + ex.Message + ""}";
            Context.Response.Write(json); 
        }

Answer 1

在c#中，访问对象的索引器只需添加[]，就像访问列表中的元素一样。JObject有一个索引器，它接受一个字符串并返回该名称的属性值。因此，您需要这样做:

            cmd.Parameters.AddWithValue("@x", OrderItem["ProductNumber"].ToString()); 

对cmd.Parameters.AddWithValue()的其他调用也是如此。