让我给您一些可能对您有帮助的事情，然后我会给您一个完整的工作示例，您应该能够自定义该示例。
首先是PdfPTable有一个特殊的方法叫做WriteSelectedRows()可以让你精确地绘制表格x,y协调。它有六种重载，但最常用的可能是：
PdfPTable.WriteSelectedRows(int rowStart,int rowEnd, float xPos, float yPos, PdfContentByte canvas)
放置表格时左上角位于400,400你会打电话：
t.WriteSelectedRows(0, t.Rows.Count, 400, 400, writer.DirectContent);
在调用此方法之前，您需要使用以下命令设置表格的宽度SetTotalWidth() first:
//Set these to your absolute column width(s), whatever they are.
t.SetTotalWidth(new float[] { 200, 300 });
第二件事是，在渲染整个表格之前，表格的高度是未知的。这意味着您无法确切知道将表格放置在何处以使其真正位于底部。解决方案是先将表格渲染到临时文档，然后计算高度。下面是我用来执行此操作的方法：
public static float CalculatePdfPTableHeight(PdfPTable table)
{
using (MemoryStream ms = new MemoryStream())
{
using (Document doc = new Document(PageSize.TABLOID))
{
using (PdfWriter w = PdfWriter.GetInstance(doc, ms))
{
doc.Open();
table.WriteSelectedRows(0, table.Rows.Count, 0, 0, w.DirectContent);
doc.Close();
return table.TotalHeight;
}
}
}
}
这可以这样调用：
PdfPTable t = new PdfPTable(2);
//In order to use WriteSelectedRows you need to set the width of the table
t.SetTotalWidth(new float[] { 200, 300 });
t.AddCell("Hello");
t.AddCell("World");
t.AddCell("Test");
t.AddCell("Test");
float tableHeight = CalculatePdfPTableHeight(t);
因此，这里有一个针对 iTextSharp 5.1.1.0 的完整工作 WinForms 示例（我知道您说的是 5.1.2，但这应该同样有效）。此示例在桌面上名为“Test”的文件夹中查找所有 JPEG。然后将它们添加到 8.5"x11" PDF 中。然后在 PDF 的最后一页上，或者如果唯一一页上只有 1 个 JPEG 开始，它会扩展 PDF 的高度，无论我们添加的表格有多高，然后将表格放在左下角角落。请参阅代码本身的注释以获得进一步的解释。
using System;
using System.Text;
using System.Windows.Forms;
using iTextSharp.text;
using iTextSharp.text.pdf;
using System.IO;
namespace Full_Profile1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public static float CalculatePdfPTableHeight(PdfPTable table)
{
//Create a temporary PDF to calculate the height
using (MemoryStream ms = new MemoryStream())
{
using (Document doc = new Document(PageSize.TABLOID))
{
using (PdfWriter w = PdfWriter.GetInstance(doc, ms))
{
doc.Open();
table.WriteSelectedRows(0, table.Rows.Count, 0, 0, w.DirectContent);
doc.Close();
return table.TotalHeight;
}
}
}
}
private void Form1_Load(object sender, EventArgs e)
{
//Create our table
PdfPTable t = new PdfPTable(2);
//In order to use WriteSelectedRows you need to set the width of the table
t.SetTotalWidth(new float[] { 200, 300 });
t.AddCell("Hello");
t.AddCell("World");
t.AddCell("Test");
t.AddCell("Test");
//Calculate true height of the table so we can position it at the document's bottom
float tableHeight = CalculatePdfPTableHeight(t);
//Folder that we are working in
string workingFolder = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "Test");
//PDF that we are creating
string outputFile = Path.Combine(workingFolder, "Output.pdf");
//Get an array of all JPEGs in the folder
String[] AllImages = Directory.GetFiles(workingFolder, "*.jpg", SearchOption.TopDirectoryOnly);
//Standard iTextSharp PDF init
using (FileStream fs = new FileStream(outputFile, FileMode.Create, FileAccess.Write, FileShare.None))
{
using (Document document = new Document(PageSize.LETTER))
{
using (PdfWriter writer = PdfWriter.GetInstance(document, fs))
{
//Open our document for writing
document.Open();
//We do not want any margins in the document probably
document.SetMargins(0, 0, 0, 0);
//Declare here, init in loop below
iTextSharp.text.Image pageImage;
//Loop through each image
for (int i = 0; i < AllImages.Length; i++)
{
//If we only have one image or we are on the second to last one
if ((AllImages.Length == 1) | (i == (AllImages.Length - 1)))
{
//Increase the size of the page by the height of the table
document.SetPageSize(new iTextSharp.text.Rectangle(0, 0, document.PageSize.Width, document.PageSize.Height + tableHeight));
}
//Add a new page to the PDF
document.NewPage();
//Create our image instance
pageImage = iTextSharp.text.Image.GetInstance(AllImages[i]);
pageImage.ScaleToFit(document.PageSize.Width, document.PageSize.Height);
pageImage.Alignment = iTextSharp.text.Image.ALIGN_TOP | iTextSharp.text.Image.ALIGN_CENTER;
document.Add(pageImage);
//If we only have one image or we are on the second to last one
if ((AllImages.Length == 1) | (i == (AllImages.Length - 1)))
{
//Draw the table to the bottom left corner of the document
t.WriteSelectedRows(0, t.Rows.Count, 0, tableHeight, writer.DirectContent);
}
}
//Close document for writing
document.Close();
}
}
}
this.Close();
}
}
}
EDIT
以下是根据您的评论进行的编辑。我只是发布内容for循环是唯一改变的部分。打电话时ScaleToFit你只需要采取tableHeight考虑到。
//Loop through each image
for (int i = 0; i < AllImages.Length; i++)
{
//Add a new page to the PDF
document.NewPage();
//Create our image instance
pageImage = iTextSharp.text.Image.GetInstance(AllImages[i]);
//If we only have one image or we are on the second to last one
if ((AllImages.Length == 1) | (i == (AllImages.Length - 1)))
{
//Scale based on the height of document minus the table height
pageImage.ScaleToFit(document.PageSize.Width, document.PageSize.Height - tableHeight);
}
else
{
//Scale normally
pageImage.ScaleToFit(document.PageSize.Width, document.PageSize.Height);
}
pageImage.Alignment = iTextSharp.text.Image.ALIGN_TOP | iTextSharp.text.Image.ALIGN_CENTER;
document.Add(pageImage);
//If we only have one image or we are on the second to last one
if ((AllImages.Length == 1) | (i == (AllImages.Length - 1)))
{
//Draw the table to the bottom left corner of the document
t.WriteSelectedRows(0, t.Rows.Count, 0, tableHeight, writer.DirectContent);
}
}
