how to append custom meta data like to PDF file?

Hello Sir,

Please tell me that how to append custom meta data like info.Add("Subject", Desc) but also not overwrite the previous meta data

i.e Subject : abc , xyz, def....etc.

string abc = Server.MapPath("~//Files//") + "new" + PAddress;

PdfStamper writer = new PdfStamper(reader, new FileStream(abc, FileMode.Create, FileAccess.Write));

Hashtable info = new Hashtable();

info.Add("Subject", Desc);

writer.MoreInfo = info;

writer.Close();

When i used this it overwrite the previous meta data with the new meta data....but i don't want to overwrite the previous one....

Please reply me as soon as possible....

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Our Advanced PDF Tools Command Line v3.0 product has this function, please download Advanced PDF Tools Command Line v3.0 from following web page to try,

https://www.verypdf.com/pdfinfoeditor/index.html#dl

https://www.verypdf.com/pdfinfoeditor/advanced_pdf_tools_cmd.zip

you can use following command lines to add new information to PDF file,

-y

There are several ways to add new information like follows:

Add new custom Properties to an existing PDF file and overwrite original custom Properties,

pdftools -i "C:\input.pdf" -o "C:\output.pdf" -y "key1=value1,key2=value2"

pdftools -i "C:\input.pdf" -o "C:\output.pdf" -y "/key1(value1) /key2(value2)"

Append new custom Properties to an existing PDF file,

pdftools -i "C:\input.pdf" -o "C:\output.pdf" -y "+key1=value1,key2=value2"

pdftools -i "C:\input.pdf" -o "C:\output.pdf" -y "+/key1(value1) /key2(value2)"

e.g.

pdftools -i "C:\input.pdf" -o "C:\output.pdf" -y "Our Company=VeryPDF Company, Support Email=support@verypdf.com, Our Web URL=https://www.verypdf.com"

pdftools -i "C:\input.pdf" -o "C:\output.pdf" -y "/Our#20Company(VeryPDF Company) /Support#20Email(support@verypdf.com) /Our#20Web#20URL(https://www.verypdf.com)"

pdftools -i "C:\input.pdf" -o "C:\output.pdf" -y "+/Our#20Company(VeryPDF Company) /Support#20Email(support@verypdf.com) /Our#20Web#20URL(https://www.verypdf.com)"

VeryPDF