为什么我的ASP.NET ListBox没有填充结果？

Question

我一直在使用DynamoDb进行ASP.NET项目，我已经从Db中提取了该项目并将其制作为新的Car对象。当我尝试填充汽车的ListBox时，似乎在ListBox中没有任何对象。这是我所拥有的：using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;using Amazon.DynamoDBv2;using Amazon.DynamoDBv2.Model;using Amazon.DynamoDBv2.DocumentModel;public partial class _Default : System.Web.UI.Page{    private static AmazonDynamoDBClient client = new AmazonDynamoDBClient();    private static string tableName = "CarTable";    private static string sampleCarReg = "05-Rn-1964";    List<car> cars = new List<car>();    protected void Page_Load(object sender, EventArgs e)    {        Amazon.DynamoDBv2.DocumentModel.Table CarTable =     Amazon.DynamoDBv2.DocumentModel.Table.LoadTable(client, tableName);        GetItemOperationConfig config = new GetItemOperationConfig        {        AttributesToGet = new List<string> { "Reg", "Manufactor", "Year",     "Problems" },            ConsistentRead = true        };        Document doc = CarTable.GetItem(sampleCarReg, config);        string Reg = doc["Reg"].AsString();        string Manufactor = doc["Manufactor"].AsString();        string Year = doc["Year"].AsString();        string Problems = doc["Problems"].AsString();       // string Model = doc["Model"].AsString();        car car1 = new car(Reg, Manufactor, Year, Problems);        cars.Add(car1);        lblCar.Text = car1.ToString();        lbxCars.DataSource = cars;    }

Answer 1

您正在设置ListBox的DataSource属性，但未指定DataTextField和DataValueField。您需要设置Car中使用的属性ListBox。

// Use what makes sense to you

lbxCars.DataSource = cars;

lbxCars.DataTextField = "Reg";

lbxCars.DataValueField = "Reg";

lbxCars.DataBind();

如果您还想选择第一项，请使用该SelectedIndex属性。当然，请务必先检查您的汽车清单中是否有物品。

if (cars.Any())

{

    lbxCars.SelectedIndex = 0;

}