C#大文件的拷贝

大文件拷贝原理：向内存申请1M空间，反复从源文件读取1M内容写入到目标文件，直到读完。

  private void CopyBigFile()
        {
            string originalPath = @"E:\AdvanceCSharpProject\LearnCSharp\21.zip";
            string destPath = @"F:\BaiduNetdiskDownload\21.zip";
            //定义读文件流
            using (FileStream fsr = new FileStream(originalPath, FileMode.Open))
            {
                //定义写文件流
                using (FileStream fsw = new FileStream(destPath, FileMode.OpenOrCreate))
                {
                    //申请1M内存空间
                    byte[] buffer = new byte[1024 * 1024];
                    //无限循环中反复读写，直到读完写完
                    while(true)
                    {
                        int readCount = fsr.Read(buffer, 0, buffer.Length);
                        fsw.Write(buffer, 0, readCount);
                        if(readCount < buffer.Length)
                        {
                            break;
                        }
                    }
                }
            }
        }