Trying to insert an image into a pdf‏ in c#

问题

I need to insert an image based on a generated barcode file.

The problem I'm having is when using the iTextSharp library I can normally fill in text such as

PdfReader pdfReader = new PdfReader(oldFile);
PdfStamper pdfStamper = new PdfStamper(pdfReader, outFile);
AcroFields fields = pdfStamper.AcroFields;
fields.SetField("topmostSubform[0].Page1[0].BARCODE[0]", "X974005-1");

though there's one field where in pdf if I click onto it it prompts me for an image to insert into field, but I can't seem to programmatically accomplish this. Based on some google searches and stumbling upon a stackoverflow page, I inserted the following code expecting it to work as desired:

string fieldName = "topmostSubform[0].Page1[0].BARCODE[0]";
string imageFile = "test-barcode.jpg";
AcroFields.FieldPosition fieldPosition = pdfStamper.AcroFields.GetFieldPositions(fieldName)[0];
PushbuttonField imageField = new PushbuttonField(pdfStamper.Writer, fieldPosition.position, fieldName);
imageField.Layout = PushbuttonField.LAYOUT_ICON_ONLY;
imageField.Image = iTextSharp.text.Image.GetInstance(imageFile);
imageField.ScaleIcon = PushbuttonField.SCALE_ICON_ALWAYS;
imageField.ProportionalIcon = false;
imageField.Options = BaseField.READ_ONLY;
pdfStamper.AcroFields.RemoveField(fieldName);               
pdfStamper.AddAnnotation(imageField.Field, fieldPosition.page);

The problem I am having is while it removes the existing field as intended, when I open the newly created PDF file I don't see this new push button field with the intended image file but rather as a blank but when I perform this through debug mode I can see that it's at least picking up the correct dimensions of the image file, so I don't know what I'm doing wrong here.

Please advise, thanks.

回答1:

If you read the official documentation (that is: my book), you'll find this example: ReplaceIcon.cs

You're removing the field using pdfStamper.AcroFields.RemoveField(fieldName); and subsequently you try adding the new field using pdfStamper.AddAnnotation(imageField.Field, fieldPosition.page);

That's wrong. You should replace the field using pdfStamper.AcroFields.ReplacePushbuttonField(fieldname, imageField.Field);

The ReplacePushbuttonField() method copies plenty of settings behind the scenes.

来源：https://stackoverflow.com/questions/15661513/trying-to-insert-an-image-into-a-pdf-in-c-sharp