在客户端电脑上下载 pdf 文件，并在下载开始后从服务器端文件夹中删除 pdf 文件

Question

这是我在客户端电脑上下载pdf的示例代码

$("#btndownload").click(function () {
    window.location = '@Url.Action("GeneratePDF", "TestModal")';
    return false;
});

public void GeneratePDF()
{
    bool IsPdfGenerated = false;

    List<Student> studentsVM = new List<Student>
    {
    new Student {ID=1,FirstName="Joy",      LastName="Roy",     FavouriteGames="Hocky"},
    new Student {ID=2,FirstName="Raja",     LastName="Basu",    FavouriteGames="Cricket"},
    new Student {ID=3,FirstName="Arijit",   LastName="Banerjee",FavouriteGames="Foot Ball"},
    new Student {ID=4,FirstName="Dibyendu", LastName="Saha",    FavouriteGames="Tennis"},
    new Student {ID=5,FirstName="Sanjeeb",  LastName="Das",     FavouriteGames="Hocky"},
    };

    var viewToString = StringUtilities.RenderViewToString(ControllerContext, "~/Views/Shared/_Report.cshtml", studentsVM, true);
    string filepath = HttpContext.Server.MapPath("~/PDFArchives/") + "mypdf.pdf";

    Document pdfDoc = null;

    try
    {
    StringReader sr = new StringReader(viewToString);
    pdfDoc = new Document(PageSize.A4, 10f, 10f, 30f, 0f);
    PdfWriter writer = PdfWriter.GetInstance(pdfDoc, new FileStream(filepath, FileMode.Create));
    pdfDoc.Open();
    XMLWorkerHelper.GetInstance().ParseXHtml(writer, pdfDoc, sr);
    pdfDoc.Close();
    IsPdfGenerated = true;
    }
    catch (Exception ex)
    {
    IsPdfGenerated = false;
    }

    System.Web.HttpContext.Current.Response.ContentType = "pdf/application";
    System.Web.HttpContext.Current.Response.AddHeader("content-disposition", "attachment;" +
        "filename=sample101.pdf");
    System.Web.HttpContext.Current.Response.Cache.SetCacheability(HttpCacheability.NoCache);
    System.Web.HttpContext.Current.Response.Write(pdfDoc);
    System.Web.HttpContext.Current.Response.End();

}

我知道 filepath 中存储的 pdf 文件路径。下载开始后，如何删除服务器端的 pdf 文件？帮助我示例代码。谢谢

Answer 1

在使用Response.End()后可以简单地使用File.Delete()方法：

System.Web.HttpContext.Current.Response.End();
System.IO.File.Delete(filepath); // add this line

如果您正在使用 FileResult 操作并从流中读取文件，您可以使用 FileOptions.DeleteOnClose while creating FileStream instance with specified file options overload:

删除文件

[HttpGet]
public FileResult GeneratePDF()
{
    // other stuff

    string filepath = HttpContext.Server.MapPath("~/PDFArchives/") + "mypdf.pdf";

    // other stuff

    var stream = new FileStream(filepath, FileMode.Open, FileAccess.Read, FileShare.None, 4096, FileOptions.DeleteOnClose);
    return File(stream, "application/pdf", "sample101.pdf"); 
}

作为替代方案，您可以创建适用于 this reference 中提供的 FileResult 操作的自定义属性。

在客户端电脑上下载 pdf 文件，并在下载开始后从服务器端文件夹中删除 pdf 文件

download pdf file at client pc and remove pdf file from server side folder after download begin

javascript

itext

asp.net-mvc-4