C#编程：File.Open获取文件字节大小

C#编程：File.Open获取文件字节大小

            OpenFileDialog p_OpenFileDialog=new OpenFileDialog();
            if (p_OpenFileDialog.ShowDialog()==DialogResult.OK)
            {
                textBox1.Text = p_OpenFileDialog.FileName;
                MessageBox.Show(
                        "文件字节大小： "+
                        File.Open(p_OpenFileDialog.FileName,FileMode.Open).Length.ToString()
                        +" 字节","提示");