C# 选择文件对话框（转自：http://blog.csdn.net/longest9/article/details/1567929）

 OpenFileDialog fileDialog1 = new OpenFileDialog();

            fileDialog1.InitialDirectory = "d://";
            fileDialog1.Filter = "xls files (*.xls)|*.xls|All files (*.*)|*.*";
            fileDialog1.FilterIndex = 1;
            fileDialog1.RestoreDirectory = true;
            if (fileDialog1.ShowDialog() == DialogResult.OK)
            {
                textBox1.Text = fileDialog1.FileName;
            }
            else
            {
                textBox1.Text = "";

            } 

注意，xls files (*.xls)|*.xls是成对出现的，前者用于描述，后者用于筛选。