Question

I’ve got a class that represents an XML file to be “processed”. I’ve created a BindingList of these objects and bound it to a DataGridView so the user (i.e. me) can “control” things a bit and “see” what’s happening. By default, the constructor assumes all files in the list will be “processed”:

public class InputFileInfo : INotifyPropertyChanged
{
    private bool processThisFile;
    public bool Process
    {
        get { return processThisFile; }
        set 
        {
            processThisFile = value;
            this.NotifyPropertyChanged("Process");
        }
    }
    public string FileName { get; set; }
    public int Rows { get; set; }
    public string Message { get; set; }
    // constructor
    public InputFileInfo(string fName)
    {
        Process = true;
        FileName = fName;
        Rows = 0;
        Message = String.Empty;
    }
    public event PropertyChangedEventHandler PropertyChanged;
    private void NotifyPropertyChanged(string name)
    {
        if (PropertyChanged != null)
            PropertyChanged(this, new PropertyChangedEventArgs(name));
    }
}

The first column of the DGV called “Process” might become unchecked in which case I want to skip that file (i.e. row) and continue with the next. The last 2 columns of the DGV are intended to display the number of output Rows that were emitted out of the processed XML file and a place to put some sort of Message (such as “OK” or “error text”).

In short, I want the DataGridView to be the visual representation of the process, echoing results in 2 little columns and allowing the user to skip a row by unchecking it.

Clicking on a button starts the processing of the files in the DGV. Here is what I have sketched so far (seems to work but the DGV does not reflect changes made in fileInfo.Rows and fileInfo.Message):

—– EDIT-UPDATE: per David Hall’s suggestion, looping thru the BindingList (_filesToParse) is a good fix to this problem (working code follows):

private void btnProcess_Click(object sender, EventArgs e)
    {
        FileStream fs = new FileStream("output-file.txt", FileMode.Create);
        StreamWriter writer = new StreamWriter(fs);
        OutputColumnNamesAsFirstLine(writer);
        foreach (InputFileInfo fileInfo in _filesToParse)
        {
            if (fileInfo.Process == true)
            {
                try
                {
                    fileInfo.Rows = processFile(writer, fileInfo.FileName);
                }
                catch (Exception ex)
                {
                    log.Warn("Error processing DataGridView:\r\n", ex);
                }
            }
            else
            {
                fileInfo.Rows = 0;
                fileInfo.Message = "skipped";
            }
        }
        writer.Dispose();
        fs.Dispose();
        MessageBox.Show("All selected files have been processed.");
    }

What would be the best approach?

• Loop through the BindingList ?
• Loop through the DataGridView ?

I think what I need is “two-way” binding but I maybe not? Am I close?

—————–E D I T (UPDATE)—————-

Yes, the XML files already exist. Here is how that part works:

private void initializeFileList(string rootFolder) // populate grid with .xml filenames to be processed
    {
        String root = rootFolder;
        var result = Directory.GetFiles(root, "*.xml", SearchOption.AllDirectories)
                    .Select(name => new InputFileInfo(name))
                    .ToList();
        _filesToParse =  new BindingList<InputFileInfo>(result.ToList());
        dataGridView1.DataSource = _filesToParse;
        dataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;
        btnProcess.Visible = true;

Answer 1

David Hall’s comment(s) gave me enough confidence to go in this direction:

• leave the datagridview as is from the toolbox to the form (i.e. do NOT loop thru the DGV)
• loop thru the BindingList collection

I took a stab at this code and posted it above by EDITing the original post. The code works but the DGV does not reflect it properly.

So, this question morphed into a different question about how to achieve 2-way binding for a datagridview which I opened in (this new thread):How to use a static utility method for property setters in a utility class