C#如何实现文件上传下载功能
这篇文章主要为大家展示了“C#如何实现文件上传下载功能”，内容简而易懂，条理清晰，希望能够帮助大家解决疑惑，下面让小编带领大家一起研究并学习一下“C#如何实现文件上传下载功能”这篇文章吧。
企业建站必须是能够以充分展现企业形象为主要目的，是企业文化与产品对外扩展宣传的重要窗口，一个合格的网站不仅仅能为公司带来巨大的互联网上的收集和信息发布平台，创新互联面向各种领域：服务器托管等成都网站设计公司、营销型网站建设解决方案、网站设计等建站排名服务。
具体代码如下所示：
//打开Excel文件，转换为DataTable
DataTable dtExcel;
private void OpenFile()
{
OpenFileDialog dialog = new OpenFileDialog();
dialog.Filter = "Microsoft Excel files(*.xls)|*.xls;*.xlsx"; //筛选打开文件类型 ：图片 *.jpg|*.jpg|*.bmp|*.bmp ;"音频文|*.mp3;*.wma;*.aac;*.midi;*.wav" 等等
if (dialog.ShowDialog() == DialogResult.OK)
{
dialogFileName = dialog.FileName;
dtExcel = ExcelToDataTable(dialogFileName, "sheet1", true);
}
}
///
/// Excel转Datatable
///
/// 文件名含后缀名
/// Excel文件，页名称
/// 是否将第一列作为表头
/// 文件下载：
private void DownLoad()
{
if (impdefineBM != null)
{
FolderBrowserDialog path = new FolderBrowserDialog();
path.ShowDialog();
if (path != null && path.SelectedPath != "")
{
string url = @"http://192.168.1.1/XX.xls"; //下载地址
string name = "FileName"; // 文件名称
string savefilepath = path.SelectedPath + "\\" + name + url.Substring(url.LastIndexOf(".")); //注意：下载文件名的命名 ，可根据实际需求调整调用的文件创建方式
MultiDownload download = new MultiDownload(5, url, savefilepath); //调用多线程下载
download.Start();
}
}
}
#region 多线程下载
public class MultiDownload
{
#region 变量
private int _threadNum; //线程数量
private long _fileSize; //文件大小
private string _fileUrl; //文件地址
private string _fileName; //文件名
private string _savePath; //保存路径
private short _threadCompleteNum; //线程完成数量
private bool _isComplete; //是否完成
private volatile int _downloadSize; //当前下载大小(实时的)
private Thread[] _thread; //线程数组
private List _tempFiles = new List();
private object locker = new object();
#endregion
#region 属性
///
/// 文件名
///
public string FileName
{
get
{
return _fileName;
}
set
{
_fileName = value;
}
}
///
/// 文件大小
///
public long FileSize
{
get
{
return _fileSize;
}
}
///
/// 当前下载大小(实时的)
///
public int DownloadSize
{
get
{
return _downloadSize;
}
}
///
/// 是否完成
///
public bool IsComplete
{
get
{
return _isComplete;
}
}
///
/// 线程数量
///
public int ThreadNum
{
get
{
return _threadNum;
}
}
///
/// 保存路径
///
public string SavePath
{
get
{
return _savePath;
}
set
{
_savePath = value;
}
}
#endregion
///
/// 构造函数
///
/// 线程数量
/// 文件Url路径
/// 本地保存路径
public MultiDownload(int threahNum, string fileUrl, string savePath)
{
this._threadNum = threahNum;
this._thread = new Thread[threahNum];
this._fileUrl = fileUrl;
this._savePath = savePath;
}
public void Start()
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(_fileUrl);
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
_fileSize = response.ContentLength;
int singelNum = (int)(_fileSize / _threadNum); //平均分配
int remainder = (int)(_fileSize % _threadNum); //获取剩余的
request.Abort();
response.Close();
for (int i = 0; i < _threadNum; i++)
{
List range = new List();
range.Add(i * singelNum);
if (remainder != 0 && (_threadNum - 1) == i) //剩余的交给最后一个线程
range.Add(i * singelNum + singelNum + remainder - 1);
else
range.Add(i * singelNum + singelNum - 1);
//下载指定位置的数据
int[] ran = new int[] { range[0], range[1] };
_thread[i] = new Thread(new ParameterizedThreadStart(Download));
_thread[i].Name = System.IO.Path.GetFileNameWithoutExtension(_fileUrl) + "_{0}".Replace("{0}", Convert.ToString(i + 1));
_thread[i].Start(ran);
}
//MessageBox.Show("下载完成！");
}
private void Download(object obj)
{
Stream httpFileStream = null, localFileStram = null;
try
{
int[] ran = obj as int[];
string tmpFileBlock = System.IO.Path.GetTempPath() + Thread.CurrentThread.Name + ".tmp";
_tempFiles.Add(tmpFileBlock);
HttpWebRequest httprequest = (HttpWebRequest)WebRequest.Create(_fileUrl);
httprequest.AddRange(ran[0], ran[1]);
HttpWebResponse httpresponse = (HttpWebResponse)httprequest.GetResponse();
httpFileStream = httpresponse.GetResponseStream();
localFileStram = new FileStream(tmpFileBlock, FileMode.Create);
byte[] by = new byte[5000];
int getByteSize = httpFileStream.Read(by, 0, (int)by.Length); //Read方法将返回读入by变量中的总字节数
while (getByteSize > 0)
{
Thread.Sleep(20);
lock (locker) _downloadSize += getByteSize;
localFileStram.Write(by, 0, getByteSize);
getByteSize = httpFileStream.Read(by, 0, (int)by.Length);
}
lock (locker) _threadCompleteNum++;
}
catch (Exception ex)
{
throw new Exception(ex.Message.ToString());
}
finally
{
if (httpFileStream != null) httpFileStream.Dispose();
if (localFileStram != null) localFileStram.Dispose();
}
if (_threadCompleteNum == _threadNum)
{
Complete();
_isComplete = true;
}
}
///
/// 下载完成后合并文件块
///
private void Complete()
{
Stream mergeFile = null;
BinaryWriter AddWriter = null;
try
{
using (mergeFile = new FileStream(@_savePath, FileMode.Create)) //根据实际情况调整FileMode
{
AddWriter = new BinaryWriter(mergeFile);
foreach (string file in _tempFiles)
{
using (FileStream fs = new FileStream(file, FileMode.Open))
{
BinaryReader TempReader = new BinaryReader(fs);
AddWriter.Write(TempReader.ReadBytes((int)fs.Length));
TempReader.Close();
}
File.Delete(file);
}
}
MyMessageBox.Show("下载完成！");
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
if (AddWriter != null)
{
AddWriter.Close();
AddWriter.Dispose();
}
if (mergeFile != null)
{
mergeFile.Close();
mergeFile.Dispose();
}
}
}
} 以上是“C#如何实现文件上传下载功能”这篇文章的所有内容，感谢各位的阅读！相信大家都有了一定的了解，希望分享的内容对大家有所帮助，如果还想学习更多知识，欢迎关注创新互联行业资讯频道！
网站标题：C#如何实现文件上传下载功能
当前网址：http://azwzsj.com/article/joihgi.html
