pdf文件创建后不保存

Question

我正在我的项目中创建一个 pdf 文件。PDF 生成工作正常。创建后，它会在浏览器中打开，但是当我点击保存链接时，它会提示保存整个页面而不是 pdf 文件。可以一个帮帮我​​好吗？ 这是我的代码：

  protected void btn_ViewSlip_Click(object sender, EventArgs e)
        {
            dt_Payslip = mm_salary.GetPayslipData(DDL_Year.SelectedValue.ToString(), DDL_Month.SelectedValue.ToString(), Session["empcd"].ToString());
            if (dt_Payslip.Rows.Count > 0)
            {
                dt_CurrPay = emp_coprofile.GetCurrExp(Session["empcd"].ToString(), DDL_Month.SelectedValue.ToString(), DDL_Year.SelectedValue.ToString());
                GenerateDisclaimerPDF();//pdf is generating here
                string url = FilesPath.Path_SaveFile + Session["empcd"].ToString() + " - Payslip.pdf";
                System.IO.FileInfo file = new System.IO.FileInfo(url);
                if (file.Exists)
                {
                    WebClient client = new WebClient();
                    Byte[] buffer = client.DownloadData(url);
                    Response.ContentType = "application/pdf";
                    Response.AddHeader("content-length", buffer.Length.ToString());
                    Response.BinaryWrite(buffer);
                }
            }
            else
            {
                msg = "Pay slip for "+DDL_Month.SelectedValue.ToString()+"-"+DDL_Year.SelectedValue+" does not exist";
            }
        }

输出：

Answer 1

那是因为你在设置

Response.ContentType = "application/pdf";

这告诉 Chrome 文件是 PDF，然后它用 PDFjs 打开它，当你点击保存时，它想要保存 PDFjs-Viewer 网页而不是 PDF。

如果您单击下载图标，则可以下载 PDF。
您需要设置 content-disposition "attachment"，并且需要将 mime-type 设置为 application/octet-stream。然后它可以在 Chrome（以及 IE 和 Firefox）中运行。

如果您想像在 Chrome 中一样在 IE 中的查看器中显示 PDF，那么您需要设置内联内容处置（IE 会忽略 mime 类型并转而使用文件扩展名）。

Dim baPDF As Byte() = GetPdfFromImage(Me.Data)

context.Response.Clear()
'context.Response.AddHeader("Content-Disposition", "attachment; filename=" + strFileName)
context.Response.AddHeader("Content-Disposition", Portal.ASP.NET.GetContentDisposition("Drucken.pdf", "inline"))
context.Response.AddHeader("Content-Length", baPDF.Length.ToString())
' context.Response.ContentType = "application/msword"
' context.Response.ContentType = "application/octet-stream"

' http://superuser.com/questions/219870/how-to-open-pdf-in-chromes-integrated-viewer-without-downloading-it#
' context.Response.ContentType = "text/html"
context.Response.ContentType = "application/pdf"

另外，请注意，如果文件名中包含 UTF-8 字符，则需要正确设置文件名标题（不同版本 [IE] 中不同浏览器的不同值）。

Public Shared Function GetContentDisposition(ByVal strFileName As String) As String
    Return GetContentDisposition(strFileName, "attachment")
End Function ' GetContentDisposition '


' http://www.iana.org/assignments/cont-disp/cont-disp.xhtml '
Public Shared Function GetContentDisposition(ByVal strFileName As String, ByVal strDisposition As String) As String
    ' http://stackoverflow.com/questions/93551/how-to-encode-the-filename-parameter-of-content-disposition-header-in-http '
    Dim contentDisposition As String
    strFileName = StripInvalidPathChars(strFileName)

    If String.IsNullOrEmpty(strDisposition) Then
        strDisposition = "inline"
    End If

    If System.Web.HttpContext.Current IsNot Nothing AndAlso System.Web.HttpContext.Current.Request.Browser IsNot Nothing Then
        If (System.Web.HttpContext.Current.Request.Browser.Browser = "IE" And (System.Web.HttpContext.Current.Request.Browser.Version = "7.0" Or System.Web.HttpContext.Current.Request.Browser.Version = "8.0")) Then
            contentDisposition = strDisposition + "; filename=" + Uri.EscapeDataString(strFileName).Replace("'", Uri.HexEscape("'"c))
        ElseIf (System.Web.HttpContext.Current.Request.Browser.Browser = "Safari") Then
            contentDisposition = strDisposition + "; filename=" + strFileName
        Else
            contentDisposition = strDisposition + "; filename*=UTF-8''" + Uri.EscapeDataString(strFileName)
        End If
    Else
        contentDisposition = strDisposition + "; filename*=UTF-8''" + Uri.EscapeDataString(strFileName)
    End If

    Return contentDisposition
End Function ' GetContentDisposition '

此外，如果您愿意接受好的建议，请摆脱

Session["empcd"]

您正在为 NullReferenceExceptions 设置自己，这完全没有必要...
尽量不要使用会话，如果可以避免的话。

哦，顺便说一句：

您应该在 WebClient 中添加 using 子句；否则你没有正确处理资源。

using(WebClient client = new WebClient())
{
       // Your code goes here
} // End Using

这将比 client.Dispose() 带来额外的好处，您无需将其放入 try-cach if-not-null-dispose 以确保之后释放资源。

Answer 2

我将代码修改为：

 protected void btn_ViewSlip_Click(object sender, EventArgs e)
    {
        dt_Payslip = mm_salary.GetPayslipData(DDL_Year.SelectedValue.ToString(), DDL_Month.SelectedValue.ToString(), Session["empcd"].ToString());
        if (dt_Payslip.Rows.Count > 0)
        {
            dt_CurrPay = emp_coprofile.GetCurrExp(Session["empcd"].ToString(), DDL_Month.SelectedValue.ToString(), DDL_Year.SelectedValue.ToString());
            GenerateDisclaimerPDF();
            string url = FilesPath.Path_SaveFile + Session["empcd"].ToString() + " - Payslip.pdf";
            System.IO.FileInfo file = new System.IO.FileInfo(url);
            if (file.Exists)
            {
                //WebClient client = new WebClient();
                //Byte[] buffer = client.DownloadData(url);
                //Response.ContentType = "application/pdf";
                //Response.AddHeader("content-length", buffer.Length.ToString());
                //Response.BinaryWrite(buffer);
               // Response.Clear();
                WebClient client = new WebClient();
                Byte[] buffer = client.DownloadData(url);
                Response.AddHeader("content-disposition", "attachment; filename=" + Session["empcd"].ToString() + " - Payslip.pdf");
                Response.AddHeader("content-length", buffer.Length.ToString());  
                Response.ContentType = "application/pdf";
                Response.BinaryWrite(buffer);
            }
        }
        else
        {
            msg = "Pay slip for "+DDL_Month.SelectedValue.ToString()+"-"+DDL_Year.SelectedValue+" does not exist";
        }
    }