Asp.net文件的上传与下载
在我们实际的应用项目开发中,文件的上传和下载都是是必不可少的,可以说是随处可见。对于DotNet下的文件上传已经是一件再简单不过的事情了,.NET提供了强大的类库System.IO 来实现IO的所有操作。对于文件的下载也是非常简单的事情,下面我将总结一些我的实际经验,希望能给初学者们一点帮助。 首先是文件的上传,文件上传必须要保证ASP.NET用户对你所要操作的服务器端文件夹有写的权限,这样剩下的事情就非常easy了,示例代码如下: ///<summary> /// 文件上传 ///</summary> ///<param name="filename">上传文件路径</param> privatebool SaveFile(filename) { string filePath=Request.PhysicalApplicationPath+"\\"+filename; try { this.excelfilepath.PostedFile.SaveAs(filePath); returntrue; } catch(UnauthorizedAccessException ex) { Response.Write("<script>alert(\"没有写入权限,访问失败!详情:"+ex.ToString()+"\");</script>"); returnfalse; } catch(Exception ex) { Response.Write("<script>alert(\"文件上传失败!详情:"+ex.ToString()+"建议:文件可能太大!\");</script>"); returnfalse; } } 对于文件的下载我总结了两种方法,其实都是大同小异,示例代码如下: 方法一: ///<summary> /// 文件下载 ///</summary> ///<param name="filename">下载文件物理路径</param> publicstaticvoid DownLoadFile(string path) { System.Web.HttpContext contxt=System.Web.HttpContext.Current; if (path !="") { //string path = HttpContext.Current.Server.MapPath(filename); System.IO.FileInfo file =new System.IO.FileInfo(path); if (file.Exists) { contxt.Response.Clear(); contxt.Response.AddHeader("Content-Disposition", "attachment; filename="+ contxt.Server.UrlEncode(file.Name)); contxt.Response.AddHeader("Content-Length", file.Length.ToString()); contxt.Response.ContentEncoding=System.Text.Encoding.Default; contxt.Response.Charset="gb2312"; contxt.Response.ContentType ="application/octet-stream"; contxt.Response.Filter.Close(); contxt.Response.WriteFile(file.FullName); contxt.Response.End(); } else { contxt.Response.Write("This file does not exist."); } } } 方法二: ///<summary> /// 文件下载 ///</summary> ///<param name="filepath"></param> publicstaticvoid DownLoadFileStream(string filepath) { System.Web.HttpContext contxt=System.Web.HttpContext.Current; if(!File.Exists(filepath)) { thrownew Exception("该文件不存在!"); } //读取文件 FileStream DownFiles = File.OpenRead(filepath); byte[] fileCont =newbyte[DownFiles.Length]; DownFiles.Read(fileCont,0,(int)DownFiles.Length); contxt.Response.Clear(); contxt.Response.AddHeader("Content-Disposition", "attachment; filename="+ contxt.Server.UrlEncode(DownFiles.Name)); contxt.Response.AddHeader("Content-Length", DownFiles.Length.ToString()); contxt.Response.ContentEncoding=System.Text.Encoding.Default; contxt.Response.Charset="gb2312"; contxt.Response.BinaryWrite(fileCont); contxt.Response.End(); }