我的代码可以很好地在 abcpdf 的一页内居中 html。这是由创建 abcpdf 的 websupergoo 公司提供给我的。但是,我的应用程序池不断关闭,我认为这是一个性能问题。我什至启用了缓存。反正有没有优化这段代码。基本上发生的事情是代码调用 html 页面,并计算出边界尺寸以设置浏览器宽度,使其适合 pdf 尺寸。这样做会一遍又一遍地调用 html 页面,但有人告诉我,如果它被缓存,它不会发出实际请求,而是读取缓存。必须有一种更简单的方法来执行此操作,因为渲染确实需要一段时间。当多个请求同时使用 abcpdf 的 url 时,似乎会发生此问题。
using (var doc = new Doc())
{
doc.HtmlOptions.Timeout = 60000;
doc.HtmlOptions.PageCacheEnabled = true;
doc.HtmlOptions.PageCacheExpiry = 600000;
doc.HtmlOptions.Engine = Engine;
doc.Rect.Inset(PageInsetHorizontal, PageInsetVertical);
doc.Color.String = "255, 255, 255";
const double heightTolerance = 18; // in points, the max allowed space at the bottom
const int widthIncrement = 96; // in pixels, just an appropriate initial browser width increment
var tallWidth = 0; // the lower browser width
var wideWidth = 0; // the upper browser width
Debug.WriteLine("Adding Url: " + Url);
var id = doc.AddImageUrl(Url);
var scrollWidth = doc.GetInfoInt(id, "ScrollWidth");
var contentWidth = doc.GetInfoInt(id, "ContentWidth");
var toContentWidth = contentWidth - scrollWidth;
while (true)
{
var width = doc.GetInfoInt(id, "ContentWidth");
var height = doc.GetInfoInt(id, "ContentHeight");
Debug.WriteLine("Initial Content Width: " + width);
Debug.WriteLine("Initial Content Height: " + height);
var tooTall = false;
var docScrollWidth = doc.GetInfoInt(id, "ScrollWidth");
Debug.WriteLine("Scroll Width: " + docScrollWidth);
if (docScrollWidth < scrollWidth)
{
scrollWidth = docScrollWidth;
contentWidth = scrollWidth + toContentWidth;
Debug.WriteLine("New Scroll Width: " + scrollWidth);
Debug.WriteLine("New Content Width: " + contentWidth);
}
Debug.WriteLine("Width: " + width);
if (width + 1 < contentWidth)
{
Debug.WriteLine("Too Tall: " + Url);
tooTall = true;
}
// assuming doc.Rect originally specifies the maximum bounding area
if (tooTall || doc.Rect.Width * height > doc.Rect.Height * width)
{
Debug.WriteLine("TOO TALL");
Debug.WriteLine("Delete Html: " + id);
// too tall
doc.Delete(id);
Debug.WriteLine("Browser Width: " + doc.HtmlOptions.BrowserWidth);
if (doc.HtmlOptions.BrowserWidth == 0)
{
doc.HtmlOptions.BrowserWidth = Convert.ToInt32(height*doc.Rect.Width/doc.Rect.Height);
Debug.WriteLine("New BrowserWidth: " + doc.HtmlOptions.BrowserWidth);
}
else
{
tallWidth = doc.HtmlOptions.BrowserWidth;
Debug.WriteLine("Tall Width: " + tallWidth);
Debug.WriteLine("Wide Width: " + wideWidth);
if (wideWidth == 0)
{
doc.HtmlOptions.BrowserWidth = tallWidth + widthIncrement;
Debug.WriteLine("New Browser Width: " + doc.HtmlOptions.BrowserWidth);
}
else if (tallWidth + 1 < wideWidth)
{
doc.HtmlOptions.BrowserWidth = (tallWidth + wideWidth)/2;
Debug.WriteLine("New Browser Width: " + doc.HtmlOptions.BrowserWidth);
}
else
{
doc.HtmlOptions.BrowserWidth = wideWidth;
Debug.WriteLine("New Browser Width: " + doc.HtmlOptions.BrowserWidth);
Debug.WriteLine("Adding Url: " + Url);
Debug.WriteLine("Found Fit");
doc.AddImageUrl(Url);
break;
}
}
}
else if (doc.Rect.Width * height < (doc.Rect.Height - heightTolerance) * width)
{
Debug.WriteLine("TOO WIDE");
Debug.WriteLine("Browser Width: " + doc.HtmlOptions.BrowserWidth);
// too wide
if (doc.HtmlOptions.BrowserWidth == 0)
{
doc.HtmlOptions.BrowserWidth = Convert.ToInt32(height * doc.Rect.Width / doc.Rect.Height);
Debug.WriteLine("New Browser Width: " + doc.HtmlOptions.BrowserWidth);
}
else
{
wideWidth = doc.HtmlOptions.BrowserWidth;
Debug.WriteLine("Tall Width: " + tallWidth);
Debug.WriteLine("Wide Width: " + wideWidth);
if (tallWidth == 0)
{
doc.HtmlOptions.BrowserWidth = wideWidth >= 2 * widthIncrement ? wideWidth - widthIncrement : wideWidth / 2;
Debug.WriteLine("New Browser Width: " + doc.HtmlOptions.BrowserWidth);
}
else if (tallWidth + 1 < wideWidth)
{
doc.HtmlOptions.BrowserWidth = (tallWidth + wideWidth)/2;
Debug.WriteLine("New Browser Width: " + doc.HtmlOptions.BrowserWidth);
}
else
{
Debug.WriteLine("Found Fit");
break;
}
}
Debug.WriteLine("Delete Html: " + id);
doc.Delete(id);
}
else
break;
Debug.WriteLine("Adding Url: " + Url);
id = doc.AddImageUrl(Url);
}
using (var ms = new MemoryStream())
{
doc.Save(ms);
if (ms.CanSeek)
{
ms.Seek(0, SeekOrigin.Begin);
}
return ms.GetBuffer();
}
}