Question

Asp.net（c#）文件上传于下载

用 Asp.net（c#）设计网站怎样实现文件的上传于下载功能？用FileUpload只能实现上传下载怎么办？在线等！怎么写代码？

Answer 1

我这里有个上传的函数，下载的还没做过（新手，目前还没用到），你看看吧能不能用了。

public void Upload(string path, System.Web.UI.WebControls.FileUpload fileupload)
    {
        bool fileOK = false;
        if (FileUpload1.HasFile)
        {
            string fileException = System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();
            //获取指定路劲字符串的后缀名，并转化为小写
            string[] allowExcption = { ".jpg", ".jpeg", ".bmp",".gif" };
            //定义允许的后缀名
            for (int i = 0; i < allowExcption.Length; i++)
            {
                if (fileException == allowExcption[i])
                {
                    fileOK = true;
                }
            }
        }

        if (fileOK)
        {
            //判断文件是否存在，若不在则创建路径
            if (System.IO.Directory.Exists(path))
            {
                //MessageBox.Show("该目录已经存在","信息提示");
            }
            else
            {
                System.IO.Directory.CreateDirectory(path);//创建文件路径
            }
            fileupload.SaveAs(path + "\\" + fileupload.FileName);//上传文件
        }
        else
        {
            Response.Write("<Script>alert('不支持此格式文件上传')</Script>");
            return;
        }
    }

 protected void Button1_Click(object sender, EventArgs e)
    {
        string serverpath = Server.MapPath("~/ImageFile");
        string imapath = "~/ImageFile/" + FileUpload1.FileName;
        Upload(serverpath, this.FileUpload1);
        Image1.ImageUrl = imapath;

        serverpath = Server.MapPath("~/ImageFile");
        imapath = "~/ImageFile/" + FileUpload1.FileName;
        Image1.ImageUrl = imapath;
        Upload(serverpath, this.FileUpload1);
    }

这部分是调用的（预览的功能），你要上传的话改成数据库操作就可以了，存放上传的路劲，文件的话她会自动生成文件夹放在里面的。

Answer 2

下载的：
//以字符流的形式下载文件
var fs = new FileStream(“服务器端文件的路径”, FileMode.Open);
var bytes = new byte[(int)fs.Length];
fs.Read(bytes, 0, bytes.Length);
fs.Close();
Response.ContentType = "application/octet-stream";
//通知浏览器下载文件而不是打开
Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode("123.txt", System.Text.Encoding.UTF8));
Response.BinaryWrite(bytes);
Response.Flush();
Response.End();

Answer 3

Response.Write

追问

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