C# 选择文件对话框（转自：http://blog.youkuaiyun.com/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。