itextsharp

插入图片

 1 using System.IO;
 2 using iTextSharp.text;
 3 using iTextSharp.text.pdf;
 4 
 5 class Program
 6 {
 7     static void Main(string[] args)
 8     {
 9         using (Stream inputPdfStream = new FileStream("input.pdf", FileMode.Open, FileAccess.Read, FileShare.Read))
10         using (Stream inputImageStream = new FileStream("some_image.jpg", FileMode.Open, FileAccess.Read, FileShare.Read))
11         using (Stream outputPdfStream = new FileStream("result.pdf", FileMode.Create, FileAccess.Write, FileShare.None))
12         {
13             var reader = new PdfReader(inputPdfStream);
14             var stamper = new PdfStamper(reader, outputPdfStream);
15             var pdfContentByte = stamper.GetOverContent(1);
16 
17             Image image = Image.GetInstance(inputImageStream);
18             image.SetAbsolutePosition(100, 100);
19             pdfContentByte.AddImage(image);
20             stamper.Close();
21         }
22     }
23 }

iTextSharp.text.Image

SetAbsolutePosition()有2个参数，第一个参数是X轴坐标，第二个参数是Y轴坐标，使用PDF坐标系，文档的左下角为坐标原点。
ScalePercent() 缩放比，

获取表单位置

 1 IList<AcroFields.FieldPosition> fieldPositions = fields.GetFieldPositions("fieldNameInThePDF");
 2 if (fieldPositions == null || fieldPositions.Count <= 0) throw new ApplicationException("Error locating field");
 3 AcroFields.FieldPosition fieldPosition = fieldPositions[0];
 4 left = fieldPosition.position.Left;
 5 right = fieldPosition.position.Right;
 6 top = fieldPosition.position.Top;
 7 bottom = fieldPosition.position.Bottom;
 8 if (rotation == 90)
 9 {
10     left = fieldPosition.position.Bottom;
11     right = fieldPosition.position.Top;
12     top = pageSize.Right - fieldPosition.position.Left;
13     bottom = pageSize.Right - fieldPosition.position.Right;
14 }

获取文字位置

1 public class RectAndText { 
2     public iTextSharp.text.Rectangle Rect; 
3     public String Text; 
4     public RectAndText(iTextSharp.text.Rectangle rect, String text) { 
5      this.Rect = rect; 
6      this.Text = text; 
7     } 
8 }

 1 public class MyLocationTextExtractionStrategy : LocationTextExtractionStrategy { 
 2     //Hold each coordinate 
 3     public List<RectAndText> myPoints = new List<RectAndText>(); 
 4 
 5     //Automatically called for each chunk of text in the PDF 
 6     public override void RenderText(TextRenderInfo renderInfo) { 
 7      base.RenderText(renderInfo); 
 8 
 9      //Get the bounding box for the chunk of text 
10      var bottomLeft = renderInfo.GetDescentLine().GetStartPoint(); 
11      var topRight = renderInfo.GetAscentLine().GetEndPoint(); 
12 
13      //Create a rectangle from it 
14      var rect = new iTextSharp.text.Rectangle(
15                bottomLeft[Vector.I1], 
16                bottomLeft[Vector.I2], 
17                topRight[Vector.I1], 
18                topRight[Vector.I2] 
19                ); 
20 
21      //Add this to our main collection 
22      this.myPoints.Add(new RectAndText(rect, renderInfo.GetText())); 
23     } 
24 }

文字位置使用代码

//Create an instance of our strategy 
var t = new MyLocationTextExtractionStrategy(); 

//Parse page 1 of the document above 
using (var r = new PdfReader(testFile)) { 
    var ex = PdfTextExtractor.GetTextFromPage(r, 1, t); 
} 

//Loop through each chunk found 
foreach (var p in t.myPoints) { 
    Console.WriteLine(string.Format("Found text {0} at {1}x{2}", p.Text, p.Rect.Left, p.Rect.Bottom)); 
}