C# Bitmap类出现参数无效异常，如何解决？

Question

Bitmap处理完最后一张图片时，出现了ms（变量）参数无效，代码如下：

 private void button4_Click(object sender, EventArgs e)
        {
            if ((textBox1.Text == null) || (textBox2.Text == null) || (or == null) || (pu == null)) {
                MessageBox.Show("请完善信息！");
            }
            else
            {
                textBox1.ReadOnly = true;
                textBox2.ReadOnly = true;
                textBox3.ReadOnly = true;
                textBox4.ReadOnly = true;
                button2.Enabled = false;
                button3.Enabled = false;
                button4.Enabled = false;
                
                string d1;
                string d2;
                List<string> na = new List<string>();
                DirectoryInfo d = new DirectoryInfo(or);
                FileInfo[] file = d.GetFiles();
                foreach (FileInfo f in file)
                {
                    na.Add(f.Name);
                }
                foreach(string filename in na) { 
                    i = 1;
                    a = 1;
                    FileInfo fpic = new FileInfo(or + @"\" + filename);
                    FileStream fs = new FileStream(or + @"\" + filename, FileMode.Open);
                    byte[] byDate = new byte[fs.Length];
                    fs.Read(byDate, 0, byDate.Length);
                    fs.Close();
                    MemoryStream ms = new MemoryStream(byDate);
                    Bitmap pic = new Bitmap(ms);
                    wi = pic.Width;
                    he = pic.Height;
                    listBox1.Items.Add(filename + "尺寸：" + wi.ToString() + "×" + he.ToString());
                    listBox1.TopIndex = listBox1.Items.Count - (int)(listBox1.Height / listBox1.ItemHeight);
                    do
                    {
                        if ((wi > (i - 1) * longth) && (wi <= i * longth))
                        {
                            d1 = ((i - 1) * longth).ToString() + "≤宽≤" + (i * longth).ToString();
                            if (!Directory.Exists(pu + @"\" + d1)) {
                                Directory.CreateDirectory(pu + @"\" + d1);
                            }
                            do
                            {
                                if ((he > (a - 1) * wideth) && (he <= a * wideth))
                                {
                                    d2 = ((a - 1) * wideth).ToString() + "≤高≤" + (a * wideth).ToString();
                                    if (!Directory.Exists(pu + @"\" + d1 + @"\" + d2))
                                    {
                                        Directory.CreateDirectory(pu + @"\" + d1 + @"\" + d2);
                                    }
                                    fpic.CopyTo(pu + @"\" + d1 + @"\" + d2 + @"\" + filename, true);
                                    ln = false;
                                } else
                                {
                                    ln = true;
                                    a++;
                                }
                            } while (ln);

                            en = false;
                        }
                        else
                        {
                            en = true;
                            i++;
                        }
                    } while (en);
                    pic.Dispose();
                    GC.Collect();
                    GC.WaitForPendingFinalizers();
                }

                listBox1.Items.Add("完成！");
                listBox1.TopIndex = listBox1.Items.Count - (int)(listBox1.Height / listBox1.ItemHeight);
                textBox1.ReadOnly = false;
                textBox2.ReadOnly = false;
                textBox3.ReadOnly = false;
                textBox4.ReadOnly = false;
                button2.Enabled = true;
                button3.Enabled = true;
                button4.Enabled = true;
            }
        
        }

异常如下：

问一下这怎么解决？

Answer 1

你为啥要通过流转来转去的，直接写bitmap.fromfile不就行了
此外，你在遍历文件夹，你确定文件夹里全是图片，没有乱七八糟别的东西吗，先判断类型再加入na，不要把非图片文件加入na