List<string> lstPath = new List<string>();
        private void FindFile(string FoldPath, string filter)//要查找的文件夹和文件类型
        {

            DirectoryInfo thefolder = new DirectoryInfo(FoldPath);
            foreach (DirectoryInfo nextfolder in thefolder.GetDirectories())
            {
                FindFile(nextfolder.FullName, filter);
            }
            foreach (FileInfo nextfile in thefolder.GetFiles(filter))
            {
                lstPath.Add(nextfile.Name);
            }

        }

------解决方案--------------------
.net 4.0的话可以直接这样
C# code
var filenames = Directory.EnumerateFiles(path, "*.*", SearchOption.AllDirectories);

------解决方案--------------------
探讨

引用:

DirectoryInfo dic = new DirectoryInfo("path");
foreach (FileInfo fi in dic.GetFiles())
{

}

可以结贴了

那我想用openfiledialog打开文件夹，我如何获得这个文件夹得路径呢？不通过filename，因为我还没有选择哪个文件来打开


------解决方案--------------------
http://langfangwangbin.blog.163.com/blog/static/100543634200981725140625/

------解决方案--------------------
new  一个FolderBrowserDialog
           if (folder.ShowDialog() == DialogResult.OK)
           {
               string path = folder.SelectedPath;
               string[] files=Directory.GetFiles(path ,"*.txt",SearchOption .AllDirectories );
                                                                                                                 foreach(string file in files )
             
                         {
                
                            string []str= Path.GetFileNameWithoutExtension(file)//你想要的文件的名字
}//自己修改下