c# - PdfArray.remove() is not removing all annotations -

i want remove annotations pdf. i'm using code:

void removeannotations(string inputpath,string outputpath)         {             pdfreader pdfreader = new pdfreader(inputpath);             pdfstamper pdfstamper = new pdfstamper(pdfreader, new filestream(outputpath, filemode.create));             pdfdictionary pagedict = pdfreader.getpagen(1);             pdfarray annotarray = pagedict.getasarray(pdfname.annots);             (int = 0; < annotarray.size; i++)             {                 annotarray.remove(i);                }             pdfstamper.close();         } 

when first create annotarray, has 217 items. after for-loop of annotarray.remove(), has 108 items, , can still see callouts , lines on pdf generated @ outputpath. it's not clear me remaining items have in common, why skipped annotarray.remove(). how can remove every annotation?

suppose have 10 elements in array:

array = [a, b, c, d, e, f, g, h, i, j] 

you loop on array this:

for (int = 0; < array.size; i++) {     array.remove(i);    } 

then happens step step:

step 0

remove element 0. result: [b, c, d, e, f, g, h, i, j]

step 1

remove element 1. result: [b, d, e, f, g, h, i, j]

step 2

remove element 2. result: [b, d, f, g, h, i, j]

step 3

remove element 3. result: [b, d, f, h, i, j]

step 4

remove element 4. result: [b, d, f, h, j]

step 5

remove element 5. there no element 5, there's nothing remove. result: [b, d, f, h, j]

step 6 9

remove element 6 9. there no element 6 9, there's nothing remove. result: [b, d, f, h, j]

although array counts 10 elements whereas yours counts 128, principle same: aren't removing annotations due logical error in code. type of array throw array out of bounds exception, pdfarray doesn't because more tolerant towards faulty pdfs incomplete arrays.

you fix code this:

int n = annotarray.size; (int = 0; < n; i++) {     annotarray.remove(0);    } 

or, found out yourself, can remove annotations @ once:

pdfreader.removeannotations();