如何填充第二个组合框。我在WPF C＃中使用Sqlite [英] How do I populate the second combobox. I am using Sqlite in WPF C#

问题描述

好的数据显示在第一个comboBox上，但当我使用基于comboBox2的selectedValue的select语句时，第二个没有任何内容。我需要做些什么来解决这个问题。



谢谢

有一个好的。

Raj

Ok the data shows up on the First comboBox, but nothing on the second when I used the select statement based on the selectedValue of comboBox2. What do I need to do here to fix this.

Thanks
Have a good one.
Raj

private void List_DistrictName()
{
  const string filename = @"C:\..\..SqliteDataFile_WithCode.db";
   
;
 var conn = new SQLiteConnection("Data Source=" + filename + ";Version=3;");
 SQLiteCommand sqlcmd = new SQLiteCommand();
 sqlcmd.Connection = conn;
 sqlcmd.CommandType = CommandType.Text;
 sqlcmd.CommandText = ("select DIST_CODE, DTNAME_ENGLISH from GramPanch_MAPPING_VIl GROUP By DTNAME_ENGLISH");

    
     DataSet ds = new DataSet();
     var sqliteDa = new SQLiteDataAdapter();
     sqliteDa.SelectCommand = sqlcmd;
 try
 {
     sqliteDa.Fill(ds, "GramPanch_MAPPING_VIl");

     DataRow nRow = ds.Tables["GramPanch_MAPPING_VIl"].NewRow();
     nRow["DTNAME_ENGLISH"] = "District All";
     nRow["DIST_CODE"] = "0";
     ds.Tables["GramPanch_MAPPING_VIl"].Rows.InsertAt(nRow, 0);

     //Binding the data to the combobox.
     comBox1.DataContext = ds.Tables["GramPanch_MAPPING_VIl"].DefaultView;

     //To display DISTNAME (DisplayMember in Visual Studio 2012)
     comBox1.DisplayMemberPath = ds.Tables["GramPanch_MAPPING_VIl"].Columns["DTNAME_ENGLISH"].ToString();
     comBox1.SelectedItem = ds.Tables["GramPanch_MAPPING_VIl"].Columns["DIST_CENSUS_CD_2011"].ToString();
     //To store the DIST ID as hidden (ValueMember in Visual Studio 2012)
     //comBox1.SelectedValuePath = ds.Tables["DTNAME"].Columns["DIST_CODE"].ToString();
    //comBox1.SelectedValue = ds.Tables["GramPanch_MAPPING_VIl"].Columns["DIST_CODE"].ToString();
 }
 catch (Exception ex)
 {
     MessageBox.Show(ex.Message);
     MessageBox.Show("An error occurred while loading District Name.");
 }
 finally
 {
     sqliteDa.Dispose();
     sqlcmd.Dispose();
     conn.Dispose();
 }
}
#endregion


#region List Sub DistrictName for the ComBox2

private void List_SubDistrictName()
{

    comBox2.Items.Clear();
    const string filename = @"C:\..\..SqliteDataFile_WithCode.db";

    var conn = new SQLiteConnection("Data Source=" + filename + ";Version=3;");
    SQLiteCommand sqlcmd = new SQLiteCommand();
    sqlcmd.Connection = conn;
    sqlcmd.CommandType = CommandType.Text;
    sqlcmd.CommandText = "select SB_DIST_NAME_ENGLISH, SB_DIST_ID from GramPanch_MAPPING_VIl WHERE DIST_CODE ='" + comBox1.SelectedValue+"'"; 
      
    DataSet ds = new DataSet();
    var sqliteDa = new SQLiteDataAdapter();
    sqliteDa.SelectCommand = sqlcmd;
    try
    {
        sqliteDa.Fill(ds, "GramPanch_MAPPING_VIl");

        DataRow nRow = ds.Tables["GramPanch_MAPPING_VIl"].NewRow();
        nRow["SB_DIST_NAME_ENGLISH"] = "--Please Select the SUB District--";
        nRow["SB_DIST_ID"] = "0";
        ds.Tables["GramPanch_MAPPING_VIl"].Rows.InsertAt(nRow, 0);

        //Binding the data to the combobox.
        comBox2.DataContext = ds.Tables["GramPanch_MAPPING_VIl"].DefaultView;

     //To display Sub District name (DisplayMember in Visual Studio 2012)
        comBox2.DisplayMemberPath = ds.Tables["GramPanch_MAPPING_VIl"].Columns["SB_DIST_NAME_ENGLISH"].ToString();
        //To store the ID as hidden (ValueMember in Visual Studio 2012)
        comBox2.SelectedValuePath = ds.Tables["GramPanch_MAPPING_VIl"].Columns["SB_DIST_ID"].ToString();
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
        MessageBox.Show("An error occurred while loading Sub District Name.");
    }
    finally
    {
        sqliteDa.Dispose();
        sqlcmd.Dispose();
        conn.Dispose();
    }
}
#endregion

private void OnLoad(object sender, RoutedEventArgs e)
{
    List_DistrictName();
    List_SubDistrictName();
}

这是XAML中ComboBox代码的一部分。\





我有

SelectedIndex =0ItemsSource ={Binding}



comboBox。



谢谢!!

Here is the part of the ComboBox code in the XAML.\


I have the
SelectedIndex="0" ItemsSource="{Binding}"

for both the comboBox.

Thanks!!

推荐答案

我设法通过使用MVVM解决问题。

感谢阅读。如果有人需要帮助，请告诉我，

I manage to work a way out by using MVVM.
Thanks to reading. If anyone needs help on this let me know,

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