Arraylist and recursion problems

Ok I am new to this c# stuff. I have used c++ for a while and have to say that this new c# thing is pretty nice. Ok here is my problem. C# doesn't have vectors so I am using an arrylist instead. I don't know if you can set a type or not but I haven't. I store a list of files that I am recursively compiling as it runs through each directory. I was stupid and created a new instance of the array list each time I recursed. So I figured I need to make the arraylist global, but I don't know how to do this. Here is my code for the recursive directory listing. Let me know if you can spot something else I can do instead or if you can spot another error that I have not seen yet.

Thanks,

Matt

public ArrayList getDirectoryTreeFiles(string folderName)
{
//MessageBox.Show(folderName);
DirectoryInfo di = new directoryInfo(folderName);
DirectoryInfo [] dirNames = di.GetDirectories();

if (dirNames.Length != 0)
{
foreach (DirectoryInfo tmp in dirNames)
{
directoriesFilesString.Add(getDirectoryTreeFiles(folderName + "\\" + tmp.ToString()));
//return directoriesFilesString;
}
}
else
{
DirectoryInfo tmp = new DirectoryInfo(folderName);
FileInfo[] rgFiles = tmp.GetFiles();
foreach(FileInfo fi in rgFiles)
{
directoriesFilesString.Add(folderName + "\\" + fi.Name);
}
return directoriesFilesString;
}
return directoriesFilesString;
}

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Arraylist and recursion problems

David Paynter

hi,

i don't see anything in your code except you use return 2 times , anyway its not a big deal

here its how to convert the array list to a typed array

private void button1_Click(object sender, EventArgs e)
{
string[] mysubFilesAndFolders = null;
FolderBrowserDialog fbd = new FolderBrowserDialog();
DialogResult rslt = fbd.ShowDialog();
if (rslt == DialogResult.OK)
{
mysubFilesAndFolders = GetSubItems(fbd.SelectedPath);
}
foreach (string itm in mysubFilesAndFolders)
{
listBox1.Items.Add(itm);
}
}
private string[] GetSubItems(string DirName)
{
ArrayList collection = new ArrayList();
DirectoryInfo dirinf = new DirectoryInfo(DirName);
DirectoryInfo[] subDirs = dirinf.GetDirectories();
FileInfo[] subFiles = dirinf.GetFiles();
foreach (DirectoryInfo dir in subDirs)
{
collection.Add("<Dir> " + dir.FullName);
}
foreach (FileInfo file in subFiles)
{
collection.Add("<File>" + file.FullName);
}
return (string[])collection.ToArray(typeof(string));
}

hope this helps

Kevin C. Kelly
I was just being sily. It needed to be a string instead of an arraylist. Thanks for the timly post.
needhelp1111

hi,

to use foreach() you need to have an object and a collection from the same type like foreach(string s in items), foreach(int i in numbers) ... etc

dirs is not type of arraylist so it will through exception

what do you want to acomplish by this code

best regards
Dimitry
Let me revise my problem. I actually did make it more globally defined for the form. But this introduced a new problem that I wasn't aware of. As I recurse through the directories I currently do not have a way to check to see if the directory is empty. When the directory is empty it stores the number 104 in the array list. Why I don't know but how do I get it to check to see if the directory is empty
Lenin82
Thanks I put that other return in for testing and forgot about it. Thanks for the help I was looking for something like that. I am getting another error now with the array list.

foreach (ArrayList tmp in dirs)

When I run this statement I get an exception error in the debuger that say's it cannont convert from type system.string to system.collection.arraylist. I think it's doing this because the value in dirs is the count. The array list also includes the list of the files that need to be stored but I can't get past the count problem. What do I need to do to get past this. Any help here would be great. If you need more code let me know and I'll paste it.
Arraylist and recursion problems

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