How can i use backgorundworker with the methods that get files ?

[Chocolade1972]

I have two methods that what they do is collection directories and files lists and add them to a treeView.

What i want to do is ot put the process in a backgroundworker and also to report the process to a progressBar.


This is the first method:


private TreeNode CreateDirectoryNode(string path, string name)
{
var directoryNode = new TreeNode(name);
var directoryListing = GetDirectoryListing(path);

var directories = directoryListing.Where(d => d.IsDirectory);
var files = directoryListing.Where(d => !d.IsDirectory);

foreach (var dir in directories)
{
i ++;
directoryNode.Nodes.Add(CreateDirectoryNode(dir.FullPath, dir.Name));
int percentage = (i + 1) * 100 / 100;
backgroundWorker1.ReportProgress(percentage);
}
foreach (var file in files)
{
directoryNode.Nodes.Add(new TreeNode(file.Name));
}
return directoryNode;
}

I added to this method the: i++ and int percentage calculation and the ReportProgress(percentage)


And this is the second method:


public IEnumerable<FTPListDetail> GetDirectoryListing(string rootUri)
{
var CurrentRemoteDirectory = rootUri;
var result = new StringBuilder();
var request = GetWebRequest(WebRequestMethods.Ftp.ListDirectoryDetails, CurrentRemoteDirectory);
using (var response = request.GetResponse())
{
using (var reader = new StreamReader(response.GetResponseStream()))
{
string line = reader.ReadLine();
while (line != null)
{
result.Append(line);
result.Append("\n");
line = reader.ReadLine();
}
if (string.IsNullOrEmpty(result.ToString()))
{
return new List<FTPListDetail>();
}
result.Remove(result.ToString().LastIndexOf("\n"), 1);
var results = result.ToString().Split(\n);
string regex =
@"^" + //# Start of line
@"(?<dir>[\-ld])" + //# File size
@"(?<permission>[\-rwx]{9})" + //# Whitespace \n
@"\s+" + //# Whitespace \n
@"(?<filecode>\d+)" +
@"\s+" + //# Whitespace \n
@"(?<owner>\w+)" +
@"\s+" + //# Whitespace \n
@"(?<group>\w+)" +
@"\s+" + //# Whitespace \n
@"(?<size>\d+)" +
@"\s+" + //# Whitespace \n
@"(?<month>\w{3})" + //# Month (3 letters) \n
@"\s+" + //# Whitespace \n
@"(?<day>\d{1,2})" + //# Day (1 or 2 digits) \n
@"\s+" + //# Whitespace \n
@"(?<timeyear>[\d:]{4,5})" + //# Time or year \n
@"\s+" + //# Whitespace \n
@"(?<filename>(.*))" + //# Filename \n
@"$"; //# End of line

var myresult = new List<FTPListDetail>();
foreach (var parsed in results)
{
var split = new Regex(regex)
.Match(parsed);
var dir = split.Groups["dir"].ToString();
var permission = split.Groups["permission"].ToString();
var filecode = split.Groups["filecode"].ToString();
var owner = split.Groups["owner"].ToString();
var group = split.Groups["group"].ToString();
var filename = split.Groups["filename"].ToString();
myresult.Add(new FTPListDetail()
{
Dir = dir,
Filecode = filecode,
Group = group,
FullPath = CurrentRemoteDirectory + "/" + filename,
Name = filename,
Owner = owner,
Permission = permission,
});
};
return myresult;
}
}
}


Then i have a GetWebRequest method


private FtpWebRequest GetWebRequest(string method, string uri)
{
Uri serverUri = new Uri("ftp://"+ uri);
if (serverUri.Scheme != Uri.UriSchemeFtp)
{
return null;
}
var reqFTP = (FtpWebRequest)FtpWebRequest.Create(serverUri);
reqFTP.Method = method;
reqFTP.UseBinary = true;
reqFTP.Credentials = new NetworkCredential(txtUsername.Text, txtPassword.Text);
reqFTP.Proxy = null;
reqFTP.KeepAlive = false;
reqFTP.UsePassive = false;
return reqFTP;
}


And a class with the FTPListDetail


public class FTPListDetail
{
public bool IsDirectory
{
get
{
return !string.IsNullOrWhiteSpace(Dir) && Dir.ToLower().Equals("d");
}
}
internal string Dir { get; set; }
public string Permission { get; set; }
public string Filecode { get; set; }
public string Owner { get; set; }
public string Group { get; set; }
public string Name { get; set; }
public string FullPath { get; set; }
}



What i need it to do is:


To work in the backgroundworker dowork event.

To report to the progressBar

And in the end in the completed event to report when the operation finished.


This is the backgroundworker dowork event:


private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
var root = txtHost.Text;
treeView1.Nodes.Clear();
treeView1.Nodes.Add(CreateDirectoryNode(root, "root"));
}


I tried in the DoWork event to put the code in invoke but it didnt help the whole program freeze.

Without invoke im getting erorr/exception in green in the DoWork event that i need to invoke it.


This is the ProgressChanged event also not sure if im doing it right here:


private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
//this.toolStripStatusLabel2.Text = e.UserState.ToString();
this.toolStripProgressBar2.Value = Math.Min(this.toolStripProgressBar2.Maximum, e.ProgressPercentage);
}


And the completed event is empty now.

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