Question

我在代码中创建了两个组合框。第一个我用来表示德国城市名称像弗伦斯堡，基尔，吕贝克。它以组合框的方式显示

   Flensburg
   Kiel
   Lübeck

我从.xls文件中获取此列表。我是一个单独的类来获取此值。我用来获取此值的代码如下

            class PlaceList
                {

                    public static ComboBox Combo_list = new ComboBox();
                    public static DataGridView dataTable = new DataGridView();

                    public static void List()
                    {

                        var startPath = Application.StartupPath;
                        string folderName = Path.Combine(startPath, "POI_List");
                        System.IO.Directory.CreateDirectory(folderName);
                        string SavedfileName = "POI_list.json";
                        var Saving_path = Path.Combine(folderName, SavedfileName);

                        string fileName = "Zensus_Gemeinden_org.xlsx";
                        var path = Path.Combine(startPath, fileName);

                        String name = "Gemeinden_31.12.2011_Vergleich";
                        String constr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" +
                                       path + ";Extended Properties='Excel 12.0 XML;HDR=YES;';";

                        OleDbConnection con = new OleDbConnection(constr);
                        OleDbCommand oconn = new OleDbCommand("Select [3] as City,[4] as Population, * From [" + name + "$D7:E11300] Where [4] > 10000", con);
                        con.Open();

                        OleDbDataAdapter sda = new OleDbDataAdapter(oconn);
                        DataTable data = new DataTable();

                        sda.Fill(data);
                        dataTable.DataSource = data;



                        for (int i = 0; i < data.Rows.Count; i++)
                        {
                            Combo_list.Items.Add(data.Rows[i]["City"]);
                        }


                        string Place_Json = "Place_List:" + JsonConvert.SerializeObject(data, Formatting.Indented);
                        File.WriteAllText(Saving_path, Place_Json);

                    }
                }

然后在form1.cs中我称这个城市名称如下

 public Form1()
    {

        InitializeComponent();


        PlaceList.Combo_list = comboBox1;
    }

这部分对我来说非常合适。现在下一步是阅读一个文本文件，我为每个地方列表写了几个兴趣点

   Flensburg,Berlin Wall,Brandenburg Gate,Reichstag Building
   Kiel,Nymphenburg palace,Museum Island,Marienplatz
   Lübeck,Old Castle,Staatsgalerie Stuttgart,schlossplatz stuttgart

我想根据第一个combobox1的点击获得此值。假如有人点击弗伦斯堡，他可以看到第二个组合框中的每个值。为了得到这个，我在Form1.cs中使用以下代码

  Dictionary<string, List<string>> poi = new Dictionary<string, List<string>>();
      private void LoadKeys()
    {

       foreach (string line in File.ReadLines("TextFile1.txt"))
                {
                    string[] parts = line.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
                    poi.Add(parts[0], new List<string>(parts.Skip(1)));
                }

    }

    void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (comboBox1.SelectedItem != null)
        {
            string txt = comboBox1.SelectedItem.ToString();
            if (poi.ContainsKey(txt))
            {
                List<string> points = poi[txt];
                comboBox2.Items.Clear();
                comboBox2.Items.AddRange(points.ToArray());
            }
        }
    }

但它根本不起作用。它对组合框2没有任何价值。我可以用不同的方式做到这一点。很抱歉有很长的描述。

使用c＃根据第一个组合框中的键从文本中获取第二个组合框中的值

0 个答案: