在ASP.NET中生成文件托管

Question

I'd like to prompt the user to download a file, generate it once they accept, and delete the file once they have made the transfer (if they accept the download.)

Does anyone know the c sharp or html code to achieve something like this?

Thanks.

Answer 1

You can use a file handler ashx for that eg, download.ashx and here is a fast example what you can have inside...

public void ProcessRequest(HttpContext context)
{
    // example for the csv
    context.Response.ContentType = "text/html";
    // what is the file name that the user see to save
    context.Response.AppendHeader("Content-disposition", "attachment; filename=" + cFileNameToShowAndDownload);

    context.Response.Write("here is your text to send");

    context.Response.Flush();
}

Answer 2

When the user accepts the download (ie. click on a button):

1. Generate CSV file and save it to temporary folder (use File class utility methods to get a temporary path)

2. Use

   Response.ContentType = "text/csv"; Response.AppendHeader("Content-disposition", "attachment; filename=file.csv");

3. Call Response.WriteFile passing the file path as argument, as generated before, then Response.Flush() to make sure all the file was sent

4. finally , delete the file