c#程序里给生成的word添加页码例如第几页共几页

Question

1，我通过程序生成一个word，这个word本身是一个模板，通过标签的方式添加进去内容，然后在把其他文件复制粘贴到这个目标word的后面
2，现在出现的问题是，模板自带的3页word可以实现页码的显示
3，但是后面添加进去的其他页面的页码就不正确了，比如总共是12页，那么除了前面3页之外，其余9页的页码都是“第12页 共12页”

            int pageCount = doc.ComputeStatistics(Word.WdStatistic.wdStatisticPages, oMissing);
            for (int i = 3; i <= pageCount; i++)
            {
                Word.Range range = GetPages(doc, i);
                object oCollapseEnd = Word.WdCollapseDirection.wdCollapseEnd;
                object oPageBreak = Word.WdBreakType.wdSectionBreakContinuous;//分页符     
                //range.Collapse(ref oCollapseEnd);  
                range.InsertBreak(ref oPageBreak);
                //range.Collapse(ref oCollapseEnd);
            }
            
            int j = 1;
            Word.Range allRange = doc.Range(ref oMissing, ref oMissing);
            foreach (Word.Section section in allRange.Sections)
            {
                //设置页脚的文字格式
                section.Footers[Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].LinkToPrevious = false;
                //页脚文字居中
                section.Footers[Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range.ParagraphFormat.Alignment = Word.WdParagraphAlignment.wdAlignParagraphCenter;
                //页脚文字字体
                section.Footers[Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range.Font.Name = "宋体";
                section.Footers[Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range.Font.Size = 10.5f;
                section.Footers[Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range.Font.Bold = 0;
                section.Footers[Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range.Text = "第" + j.ToString() + "页";
                j++;
            }