System.ObjectDisposedException: 'Cannot read from a closed TextReader.'

user_19009910 0
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For my homework I have to make a XAML project using a csv file to show pictures of zoo animals along with other info which is included in the code.

It's almost done but when I run the program it gives me this error:

System.ObjectDisposedException: 'Cannot read from a closed TextReader.'

private async void Button_Click(object sender, RoutedEventArgs e)
{
    var picker = new Windows.Storage.Pickers.FileOpenPicker();
    picker.FileTypeFilter.Add(".csv");
    var file = await picker.PickSingleFileAsync();

    if (file == null)
    {
        tbFileStatus.Text = "(not a valid file chosen)";
        return;
    }

    tbFileStatus.Text = file.Path;

    using (var fileAccess = await file.OpenReadAsync())
    {
        using (var stream = fileAccess.AsStreamForRead())
        {
            using (var reader = new StreamReader(stream))
            {
                using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture))
                {
                    var lvAnimals = csv.GetRecords<Animal>();
                }

                while (!reader.EndOfStream)
                {
                    var row = reader.ReadLine();
                    var parts = row.Split(',');
                    var number = (parts[0]);
                    var name = parts[1];
                    var species = parts[2];
                    var latin_name = parts[3];
                    var cage = parts[4];
                    var picture = parts[5];
                    var llvAnimals = new Animal
                    {
                        Number = number,
                        Name = name,
                        Species = species,
                        Latin_Name = latin_name,
                        Cage = cage,
                        Picture = picture
                    };
                    lvAnimals.ItemsSource = llvAnimals;
                }                                
            }
        }
    }
}
c#
1 Answers

You are passing your StreamReader to the CsvReader.

using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture))
{
    ...
}
while (!reader.EndOfStream)
...

By making use of using, you are disposing the CsvReader after its usage. Keep in mind, that some implementations like this also disposing their readers. This can be seen in the corresponding implementation. This means, the passed StreamReader gets also closed and can't be used afterwards. This causes the System.ObjectDisposedException.

To solve this, extend the usage scope like this:

using (var reader = new StreamReader(stream))
using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture))
{
    ...
    while (!reader.EndOfStream)
    ...
}
user_52355740
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