ASP.NET文件下载函数使用浅析

ASP.NET文件下载函数使用是什么情况呢？在你的Page_Load中添加这样的代码:

Page.Response.Clear();  
bool success = ResponseFile(Page.Request, Page.Response, "目的文件名称", @"源文件路径", 1024000);  
 if (!success)  
     Response.Write("下载文件出错！");  
Page.Response.End(); 

ASP.NET文件下载函数代码为:

public static bool ResponseFile(HttpRequest _Request,HttpResponse _Response,string _fileName,string _fullPath, long _speed)  
    {  
        try 
        {  
            FileStream myFile = new FileStream(_fullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);  
            BinaryReader br = new BinaryReader(myFile);  
            try 
            {  
                _Response.AddHeader("Accept-Ranges", "bytes");  
                _Response.Buffer = false;  
                long fileLength = myFile.Length;  
                long startBytes = 0;  
       
                double pack = 10240; //10K bytes  
                //int sleep = 200;   //每秒5次   即5*10K bytes每秒  
                int sleep = (int)Math.Floor(1000 * pack / _speed) + 1;  
                if (_Request.Headers["Range"] != null)  
                {  
                    _Response.StatusCode = 206;  
                    string[] range = _Request.Headers["Range"].Split(new char[] {'=', '-'});  
                    startBytes = Convert.ToInt64(range[1]);  
                }  
                _Response.AddHeader("Content-Length", (fileLength - startBytes).ToString());  
                if (startBytes != 0)  
                {  
                    //Response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", startBytes, fileLength-1, fileLength));  
                }  
                _Response.AddHeader("Connection", "Keep-Alive");  
                _Response.ContentType = "application/octet-stream";  
                _Response.AddHeader("Content-Disposition","attachment;filename=" + HttpUtility.UrlEncode(_fileName,System.Text.Encoding.UTF8) );  
               
                br.BaseStream.Seek(startBytes, SeekOrigin.Begin);  
                int maxCount = (int) Math.Floor((fileLength - startBytes) / pack) + 1;  
 
                for (int i = 0; i < maxCount; i++)  
                {  
                    if (_Response.IsClientConnected)  
                    {  
                        _Response.BinaryWrite(br.ReadBytes(int.Parse(pack.ToString())));  
                        Thread.Sleep(sleep);  
                    }  
                    else 
                    {  
                        i=maxCount;   
                    }  
                }  
            }  
            catch 
            {  
             return false;  
            }  
            finally  
            {  
                br.Close();  
 
                myFile.Close();  
            }  
        }  
        catch 
        {  
            return false;  
        }  
        return true;  
    } 

这样就实现了文件下载时,不管是什么格式的文件,都能够弹出打开/保存窗口.

ASP.NET文件下载函数的基本情况就向你介绍到这里，希望对你了解ASP.NET文件下载函数有所帮助。

【编辑推荐】

1. ASP.NET项目开发中健康监视浅析
2. ASP.NET缓存概念及其应用浅析
3. ASP.NET缓存分析和实践浅析
4. ASP.NET数据库缓存浅析
5. ASP.NET源码之自定义控件DateTimePicker