Question

我尝试将数据添加到列表中，然后将其添加到另一个列表`{

{
    "name": "0001",
    "id": "donut",
    "total": {
        "price": [{
                "date": "1001",
                "type": "Regular"
            },
            {
                "id": "1002",
                "type": "Chocolate"
            },
            {
                "id": "1003",
                "type": "Blueberry"
            },
            {
                "id": "1004",
                "type": "Devil's Food"
            }
        ]
    }
}

这就是输出Json的样子。以下是我的一些代码：

public class TotalPrice
{
  public string date { get; set; }
  public string price { get; set; }
}

public class TotalPrices
{
  public List<TotalPrice> Price { get; set; }
}

public class AgencyCompare
{
  public string name { get; set; }
  public string id { get; set; }
  public TotalPrices total { get; set; }
}

for (int j = 0; j < dtFIT.Rows.Count; j++)
{
  var xTrans = new AgencyCompare();
  var xxx = new List<TotalPrice>();
  Debug.WriteLine("Start xTrans.ID");
  xTrans.id = id[j];
  Debug.WriteLine("End xTrans.ID");
  Debug.WriteLine("Start xTrans.name");
  xTrans.name = name[j];
  Debug.WriteLine("End xTrans.name");
  if (rowCount[j] > 0)
  {
    Debug.WriteLine("ROWCOUNT > 0");
    for (int z = 0; z < rowCount[j]; z++)
    {
      Debug.WriteLine("Start xTrans2");
      var xTrans2 = new TotalPrice();
      Debug.WriteLine("Start xTrans2.date");
      xTrans2.date = AtDay[j, z];
      Debug.WriteLine("End xTrans2.date");
      Debug.WriteLine("Start xTrans2.price");
      xTrans2.price = TotalPrice[j, z];
      Debug.WriteLine("End xTrans2.price");
      xxx.Add(xTrans2);
      Debug.WriteLine("xTrans.total.Price.Add(xTrans2)");
    }
    xTrans.total.Price.AddRange(xxx);
  }
  else
  {
    //
  }
  //xTrans.date = AtDay[j];
  //xTrans.total = TotalPrice[j];
  Debug.WriteLine("xAryTransCheckIn.Add(xTrans)");
  xAryTransCheckIn.Add(xTrans);
}
return xAryTransCheckIn;

我调试时的错误：

启动xTrans2

启动xTrans2.date

结束xTrans2.date

启动xTrans2.price

结束xTrans2.price

xTrans.total.Price.Add（xTrans2）

启动xTrans2

启动xTrans2.date

结束xTrans2.date

启动xTrans2.price

结束xTrans2.price

xTrans.total.Price.Add（xTrans2）

启动xTrans2

启动xTrans2.date

结束xTrans2.date

启动xTrans2.price

结束xTrans2.price

xTrans.total.Price.Add（xTrans2）

抛出异常：＆＃39; System.NullReferenceException＆＃39;在Webrestful.dll`中

当我调用xTrans.total.Price.AddRange（xxx）;时，抛出异常，我不确定我是否设置了正确的类格式，或者当我尝试添加列表时出错

Answer 1

您遗失了xTrans.total =new TotalPrices()和xTrans.total.Price = new List<TotalPrice>()

JSON将列表<class>添加到类xxx

1 个答案: