OpenFileDialog对话框影响当前工作目录，比如，当前工作目录为一个项目的bin/debug目录下，配置文件也在这下面，当OpenFileDialog选择文件时，目录改为选择文件所在目录，这样程序中的  xmlDoc.Load("FileTyp.xml");就找不到文件FileTyp.xml了，解决此问题是方法是，OpenFileDialog之前保存一下当前目录，之后再还原：如下：

       private void butSelectFile_Click(object sender, EventArgs e)
        {
            string curWD = System.IO.Directory.GetCurrentDirectory();
            OpenFileDialog fd = new OpenFileDialog();
            if (fd.ShowDialog(this) == DialogResult.OK)
            {           
                localFileName = fd.SafeFileName;
                FileInfo fi = new FileInfo(fd.SafeFileName);
                String path = fi.Directory.ToString();
                this.localFilePath = path + "\\" + localFileName;
                textFile.Text = localFilePath;
               
            }
            System.IO.Directory.SetCurrentDirectory(curWD);

        }