为什么我的 PDF 请求无法使用“请求”？

发布于 2024-09-05 03:22:28 字数 1712 浏览 4 评论 0原文

我们正在尝试创建一个 .NET aspx 页面，其中包含 PDF。通过硬编码来做到这一点很容易。

<object height="1250px" width="100%" type="application/pdf" data="our.pdf">
    <param value="our.pdf" name="src" />
    <param value="transparent" name="wmode" />
</object>

（不要太担心透明的事情......我们这样做是出于其他原因......但我将其包含在这里“以防万一”。）

问题是当我们想要动态生成 PDF 时。我们在前端填充文字的代码如下所示：

ltrPDF.Text = String.Format("<object height=\"1250px\" width=\"100%\" type=\"application/pdf\" data=\"ourPdfGenerator.aspx?var0={0}&var1={1}&var2={2}\">", var0, var1, var2);
ltrPDF.Text += String.Format("<param value=\"ourPdfGenerator.aspx?var0={0}&var1={1}&var2={2}\">", var0, var1, var2);
ltrPDF.Text += "<param value=\"transparent\" name=\"wmode\"/>";
ltrPDF.Text += "</object>";

有点难看，但看起来应该可以工作。但事实并非如此。

当我调试并在 PdfGenerator.aspx.cs Page_Load 方法的第一行放置断点时，我毫无困难地到达断点。然而，我们做的第一件事是尝试使用Request.QueryString：

string var0 = Request.QueryString["var0"];

它会立即抛出一个HttpException：“请求在此上下文中不可用。”我不清楚：

为什么不可用？
我能做什么呢？

编辑：（顺便说一句，我知道从 aspx 页面请求 mime 类型的 pdf 似乎有点奇怪......但是我们之前使用过 aspx 页面来生成 cs 页面......我们做了类似的事情this：

Response.Clear();
Response.ContentType = "application/pdf";
Response.AddHeader("Content-Disposition", "attachment;filename=\"our.pdf\"");
using (MemoryStream pdfStream = new MemoryStream())
{
    ourSpecialPdfGenerator.ExportToPdf(pdfStream);
    Response.BinaryWrite(pdfStream.ToArray());
}
Response.End();

这在其他上下文中已经运行良好一段时间了...但始终作为其自己的页面，我们现在所做的不同之处是我们尝试嵌入它，而不是直接调用该页面，所以它是这样的。从

原文

We're trying to create a .NET aspx page that will have a PDF within it. Doing this by hardcoding it is easy.

<object height="1250px" width="100%" type="application/pdf" data="our.pdf">
    <param value="our.pdf" name="src" />
    <param value="transparent" name="wmode" />
</object>

(don't worry too much about the transparent thing...we're doing that for other reasons...but I include it here "just in case".)

The problem is when we want to generate the PDF dynamically. Our code to populate the literal on the front end looks like this:

ltrPDF.Text = String.Format("<object height=\"1250px\" width=\"100%\" type=\"application/pdf\" data=\"ourPdfGenerator.aspx?var0={0}&var1={1}&var2={2}\">", var0, var1, var2);
ltrPDF.Text += String.Format("<param value=\"ourPdfGenerator.aspx?var0={0}&var1={1}&var2={2}\">", var0, var1, var2);
ltrPDF.Text += "<param value=\"transparent\" name=\"wmode\"/>";
ltrPDF.Text += "</object>";

Kind of ugly, but it seems like it should work. But it doesn't.

When I debug, and put a breakpoint on the first line of ourPdfGenerator.aspx.cs Page_Load method, I reach the breakpoint without any difficulty. However, the first thing we do is try to use Request.QueryString:

string var0 = Request.QueryString["var0"];

which immediately throws an HttpException: "Request is not available in this context." I'm not clear on:

Why isn't it available?
What can I do about it?

EDIT: (as an aside, I know it seems a bit weird to ask for a mime-type of pdf from a aspx page...but we've used an aspx page to generate cs pages before...we do something like this:

Response.Clear();
Response.ContentType = "application/pdf";
Response.AddHeader("Content-Disposition", "attachment;filename=\"our.pdf\"");
using (MemoryStream pdfStream = new MemoryStream())
{
    ourSpecialPdfGenerator.ExportToPdf(pdfStream);
    Response.BinaryWrite(pdfStream.ToArray());
}
Response.End();

And this has been working fine in other contexts for a while...but always as its own page. What we're doing differently now is instead of having this page called directly, we're trying to embed it, so it's being called from the <object> tag, which is apparently causing problems...

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