在代码中使用System.Data.OleDb命名空间时找不到OleDbConnection

Question

i have read the other question with the same one without the OldeDb namespace in it. But I am still having a problem

I am creating a UWP app, and I want to upload a data from an Excel file to a DataGridView.

So this is my code

This is my reference code

using System.Collections.Generic;
using Windows.UI.Xaml.Controls;
using System.Data;
using Microsoft.Toolkit.Uwp.UI.Controls;
using System;
using System.IO;
using System.Data.OleDb

then this is my code on uploading my excel file

String constr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fullDirectory + ";Extended Properties='Excel 12.0 XML;HDR=YES;';";

OleDbConnection con = new OleDbConnection(constr);
OleDbCommand oconn = new OleDbCommand("Select * From [" + "2018" + "$]", con);

And this is my error code

Error CS0246 The type or namespace name 'OleDbCommand' could not be found (are you missing a using directive or an assembly reference?)

Any ideas why this is occurring? Thanks

Full Code

using System.Collections.Generic;
using Windows.UI.Xaml.Controls;
using System.Data;
using Microsoft.Toolkit.Uwp.UI.Controls;
using System;
using System.IO;
using System.Data.OleDb;

namespace App
{
    /// <summary>
    /// An empty page that can be used on its own or navigated to within a Frame.
    /// </summary>
    public sealed partial class MainPage : Page
    {
        public MainPage()
        {
            this.InitializeComponent();
        }

        private void SaveButton_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e)
        {

        }

        private void CancelButton_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e)
        {

        }

        private void AppBarButton_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e)
        {
            if (this.Frame.CanGoBack)
            {
                this.Frame.GoBack();
            }
        }

        private async void BtnOpenAttendanceFileDialog_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e)
        {
            var picker = new Windows.Storage.Pickers.FileOpenPicker();
            picker.ViewMode = Windows.Storage.Pickers.PickerViewMode.List;
            picker.SuggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.Desktop;
            picker.FileTypeFilter.Clear();
            picker.FileTypeFilter.Add(".xls");
            picker.FileTypeFilter.Add(".xlsx");
            picker.FileTypeFilter.Add(".dat");
            picker.FileTypeFilter.Add(".csv");


            Windows.Storage.StorageFile file = await picker.PickSingleFileAsync();
            if (file != null)
            {
                this.txtFileLocation.Text = file.Path;
            }
            else
            {

            }
        }

        private void BtnLoadFile_Click(object sender, Windows.UI.Xaml.RoutedEventArgs e)
        {
            string fileDirectory = Path.GetDirectoryName(txtFileLocation.Text.Trim());
            string fileName = Path.GetDirectoryName(txtFileLocation.Text.Trim());
            string fullDirectory = txtFileLocation.Text.Trim();

            String constr = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + fullDirectory + ";Extended Properties='Excel 12.0 XML;HDR=YES;';";

            OleDbConnection con = new OleDbConnection(constr);
            OleDbCommand oconn = new OleDbCommand("Select * From [" + "2018" + "$]", con);


        }
    }
}

Answer 1

After some digging (which can be found in the comments) I've found that you can only use a small subset of .NET in a UWP application.

Creating a simple console-application will verify that there isn't a problem with your Visual Studio installation. Eg :

namespace App
{
    static void Main(string[] args)
    {
         using(var conn = new System.Data.OleDb.OleDbConnection{connString = "..info.."})
        {
             conn.Open();
             Console.WriteLine("DS:{0} DB: {1}",conn.DataSource,conn.Database);   
        }
    }
}

Its simply that UWP does not support OleDbConnection . Please see more details here on what you can use. Also, have a look at: API's of UWP to verify that you are on the correct version.

Also, this error can be caused by having multiple reference variants to System.Data for everyone else stumbling across this answer.