【发布时间】：2019-01-22 13:15:24
【问题描述】：
这是我正在使用的 JSON 文件的结构。
{
"date": "2015-11-11",
"retailer_id": "CLD001",
"orders": [
{
"products": [
{
"product_id": "53743443003",
"quantity": 4,
"unit_price": 42.71
}
],
"value": 170.84,
"customer": {
"id": 58
}
}
]
}
为了处理这个 Json 文件，我创建了 3 个单独的类来包含 productsOrdered、OrderItems 和 RetailerOrders 的信息。是说sql无法匹配到泛型系统列表的类型？
[Table]
public class OrderItems : INotifyPropertyChanged, INotifyPropertyChanging
{
private List<ProductsOrdered> po = new List<ProductsOrdered>();
private double TotalPrice;
private int customer_id;
///this list is also throwing a error i'd suspect after the parent is fixed
[JsonProperty(PropertyName = "products")]
[Column]
///设置已订购产品的列表
public List<ProductsOrdered> Productsordered
{
get { return po; }
set
{
NotifyPropertyChanging("Products Ordered");
po = value;
NotifyPropertyChanged("Products Ordered");
}
}
[JsonProperty(PropertyName = "value")]
[Column]
public double totalprice
{
get { return TotalPrice; }
set {
NotifyPropertyChanging("Total Price");
TotalPrice = value;
NotifyPropertyChanged("Total Price");
}
}
[JsonProperty(PropertyName = "id")]
[Column(IsPrimaryKey = true, IsDbGenerated = false, AutoSync = AutoSync.OnInsert)]
public int customerid
{
get { return customer_id; }
set {
NotifyPropertyChanging("Customer_ID");
customer_id = value;
NotifyPropertyChanged("Custome_ID");
}
}
private void NotifyPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this,
new PropertyChangedEventArgs(propertyName));
}
}
private void NotifyPropertyChanging(string propertyName)
{
if (PropertyChanging != null)
{
PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
}
}
public event PropertyChangedEventHandler PropertyChanged;
public event PropertyChangingEventHandler PropertyChanging;
}
///错误源自的零售商订单 System.Data.Linq.dll 中发生“System.InvalidOperationException”类型的未处理异常
[Table]
public class RetailOrders : INotifyPropertyChanged, INotifyPropertyChanging
{
private List<OrderItems> oi;
private string retailer_id;
private DateTime date;
[Column(IsPrimaryKey = true, IsDbGenerated = false, AutoSync = AutoSync.OnInsert)]
[JsonProperty(PropertyName = "retailer_id")]
public string Retailer_id
{
get { return retailer_id; }
set {
NotifyPropertyChanging("Retailer ID");
retailer_id = value;
NotifyPropertyChanged("Retailer ID");
}
}
有关该错误的更多信息表明它源自此处，无法确定“System.Collections.Generic.List`1[SalesManagement.OrderItems]”的 SQL 类型。这让我觉得我错误地设置了列值
[JsonProperty(PropertyName = "orders")]
[Column]
public List<OrderItems> OrderItems
{
get { return oi; }
set {
NotifyPropertyChanging("OrderItems");
oi = value;
NotifyPropertyChanged("OrderItems");
}
}
[JsonProperty(PropertyName = "date")]
[Column]
public DateTime Date
{
get { return date; }
set {
NotifyPropertyChanging("date");
date = value;
NotifyPropertyChanged("date");
}
}
private void NotifyPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this,
new PropertyChangedEventArgs(propertyName));
}
}
private void NotifyPropertyChanging(string propertyName)
{
if (PropertyChanging != null)
{
PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
}
}
public event PropertyChangedEventHandler PropertyChanged;
public event PropertyChangingEventHandler PropertyChanging;
}
///这是我的 productsOrdered 表，其中包含一个具有 ID、QUANITY 和 UNIT PRICE 的对象
[Table]
public class ProductsOrdered : INotifyPropertyChanged, INotifyPropertyChanging
{
private string productID;
private int quantity;
private double unit_price;
[JsonProperty(PropertyName = "product_id")]
[Column(IsPrimaryKey = true, IsDbGenerated = false, AutoSync = AutoSync.OnInsert)]
public string ProductID
{
get { return productID; }
set
{
NotifyPropertyChanging("product ID");
productID = value;
NotifyPropertyChanged("product ID");
}
}
[JsonProperty(PropertyName = "quantity")]
[Column]
public int Quantity
{
get { return quantity; }
set {
NotifyPropertyChanging("quantity");
quantity = value;
NotifyPropertyChanged("quantity");
}
}
[JsonProperty(PropertyName = "unit_price")]
[Column]
public double UnitPrice
{
get { return unit_price; }
set {
NotifyPropertyChanging("unit price");
unit_price = value;
NotifyPropertyChanged("unit price");
}
}
private void NotifyPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this,
new PropertyChangedEventArgs(propertyName));
}
}
private void NotifyPropertyChanging(string propertyName)
{
if (PropertyChanging != null)
{
PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
}
}
public event PropertyChangedEventHandler PropertyChanged;
public event PropertyChangingEventHandler PropertyChanging;
}
通过一些调查，我相信一旦进入列表就使用 [ASSOCIATION] 而不是 [Column] 但是我不确定处理表格的正确方法是什么
【问题讨论】：
-
删除所有不必要的东西来拥有MCVE怎么样？
-
您的 customerid JsonProperty 是 id，但在 JSON 中它在 customer 下，然后 id 在括号下，会不会导致其他问题？
-
可以，但是这些类是用来创建表的
-
它在说... -- 什么是“它”？您必须按照上面的建议将其转换为 MCVE。由于缩进不良、与问题无关的属性和空白，代码很难阅读。所有这些属性都可以是自动属性。
标签： c# sql entity-framework linq