c# - Add label to pdf document itextsharp -

i'm using itextsharp join multiple pdf files 1 single file. (below write function i'm using).

now have new requirement, need set label text inside first page. label should placed on top of existing content.

i write function receives page (of type pdfimportedpage) , string parameters, modifies page adding label , returns modified page.

thanks helping

this function use:

public byte[] join(params byte[][] files) {      byte[] mergedpdf = null;      using (memorystream ms = new memorystream())      {            using (document document = new document())            {                 using (pdfcopy copy = new pdfcopy(document, ms))                 {                     document.open();                      (int = 0; < files.count(); ++i)                     {                         using (pdfreader reader = new pdfreader(files[i]))//stampeddoc))                         {                             // loop on pages in document                             int n = reader.numberofpages;                             (int page = 0; page < n; )                             {                                 var addpage = copy.getimportedpage(reader, ++page);                                 copy.addpage(addpage);                             }                         }                     }                 }                 mergedpdf = ms.toarray();             }             return mergedpdf;     } } 

update 1:

i wrote function without success.

private void addtext(pdfcopy copy, string text) {      var pagestamp = copy.createpagestamp(addpage);      var on = pagestamp.getovercontent();      overcontent.savestate();      overcontent.begintext();      basefont bf = basefont.createfont(basefont.helvetica, basefont.cp1252, basefont.not_embedded);      overcontent.setfontandsize(bf, 10 );      overcontent.settextmatrix( 100, 100);      overcontent.showtext(text);      overcontent.endtext();      overcontent.restorestate();   }