單線程讀檔案

代碼

using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using System.IO;

namespace ExToDB.FileTransfer
{
    public class FileComsumer
    {
        private string fileName;
        private Stream streamOuput = null;
        private int bufferSize = 1024;

        private Thread fileThread = null;
        private volatile bool isStop;

        public event ReturnEndEvent OnReadEnd;

        public FileComsumer(string fileName)
        {
            isStop = false;
            this.fileName = fileName;
        }

        /// <summary>
        /// 擷取讀到的Stream
        /// </summary>
        public Stream StreamOuput
        {
            get { return streamOuput; }
        }

        public void Start()
        {
            fileThread = new Thread(new ThreadStart(TheadReadFile));
            fileThread.Start();
        }

        public void Stop()
        {
            isStop = true;
            if (fileThread != null && fileThread.ThreadState == System.Threading.ThreadState.Running)
                fileThread.Abort();
            fileThread = null;
        }

        private byte[] buffer = null;

        /// <summary>
        /// 擷取讀到的資料
        /// </summary>
        public byte[] Buffer
        {
            get { return buffer; }
        }

        private void TheadReadFile()
        {
            streamOuput = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read, bufferSize, true);
            int numBytesToRead = (int)streamOuput.Length;
            int numBytesRead = 0;
            buffer = new byte[streamOuput.Length];
            while (numBytesToRead > 0 && !isStop)
            {
                // Read may return anything from 0 to numBytesToRead.
                int n = streamOuput.Read(buffer, numBytesRead, numBytesToRead);
                // The end of the file is reached.
                if (n == 0)
                {
                    OnOnReadEnd();
                    break;
                }
                    numBytesRead += n;
                numBytesToRead -= n;
                //讀取檔案完成，觸發事件
                if (numBytesToRead == 0)
                    OnOnReadEnd();
            }
            streamOuput.Close();
        }

        private void OnOnReadEnd()
        {
            if(this.OnReadEnd!=null)
                OnReadEnd(this,new ReturnEndReadEventargs(true));
        }
    }
}