c# - Adding borders and background color with iTextSharp to PdfFormField -

i want add borders , background color pdfformfield. background color activated after write text field before white. , can't borders show up.

this code:

public void addfield(pdfwriter writer, string name, int x, int y, int w, int h, pdfcontentbyte cb, int maxsize, string text, basefont font, int border)         {         rectangle rec = new rectangle(x, y-h, x+w, y);         // change font widths         //basefont font = basefont.createfont("c:\\windows\\fonts\\calibri.ttf", basefont.cp1252, basefont.not_embedded);         float fontsize = 12;          //int[] widths = font.widths;         //for (int k = 0; k < widths.length; k++)         //{         //if (widths[k] != 0)         //widths[k] = width;         //}         font.forcewidthsoutput = true;         string = "0123456789abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz-*/+.,\"'():;,?./!$+=_{[]}&éèàêîâ";          //color textcolor = basecolor.red;         // create acroform textfield          pdfformfield field = pdfformfield.createtextfield(writer, pdfformfield.singleline, pdfformfield.plaintext, maxsize);         field.fieldname = name;         field.defaultvalueasstring = text;          //ield.gettextfield();         field.mkbackgroundcolor = basecolor.red;          //field.backgroundcolor = new graycolor(0.75f);         //field.bordercolor = graycolor.grayblack;         //field.borderwidth = 1;         //field.borderstyle = pdfborderdictionary.style_beveled;          field.setfieldflags(pdfannotation.flags_print);         field.setpage();         writer.addannotation(field);          // position field on page         field.setwidget(rec, pdfannotation.highlight_invert);          // create apperance field size , font match want         pdfappearance tp = cb.createappearance(rec.right-rec.left, rec.top-rec.bottom);         pdfappearance da = (pdfappearance)tp.duplicate;         da.setfontandsize(font, fontsize);         da.setcolorfill(basecolor.red);         field.defaultappearancestring = da;          // fill default value of field          tp.beginvariabletext();         tp.savestate();         tp.rectangle(rec);         tp.clip();         tp.newpath();         tp.begintext();         tp.setfontandsize(font, fontsize);         tp.setcolorfill(basecolor.black);         tp.settextmatrix(100,100);         tp.showtext(all);         tp.settextmatrix(2,(rec.top-rec.bottom)/2-(fontsize*0.3f));         tp.showtext(text);         tp.endtext();         tp.restorestate();         tp.endvariabletext();          field.setappearance(pdfannotation.appearance_normal, tp); }