求C# 给word插入页眉的方法

调用：string text=textBox14.Text ;
report.SetPageHeader(text);
下面是封装的类
怎么完事页眉一点反应都没有 哪里不对吗？
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.Office.Interop.Word;

namespace 报告生成软件
{
class Report
{
private _Application wordApp = null;
private _Document wordDoc = null;
public _Application Application
{
get
{
return wordApp;
}
set
{
wordApp = value;
}
}
public _Document Document
{
get
{
return wordDoc;
}
set
{
wordDoc = value;
}
}

//通过模板创建新文档
public void CreateNewDocument(string filePath)
{
killWinWordProcess();
wordApp = new ApplicationClass();
wordApp.DisplayAlerts = WdAlertLevel.wdAlertsNone;
wordApp.Visible = false;
object missing = System.Reflection.Missing.Value;
object templateName = filePath;
wordDoc = wordApp.Documents.Open(ref templateName, ref missing,
ref missing, ref missing, ref missing, ref missing, ref missing,
ref missing, ref missing, ref missing, ref missing, ref missing,
ref missing, ref missing, ref missing, ref missing);
}

//保存新文件
public void SaveDocument(string filePath)
{
object fileName = filePath;
object format = WdSaveFormat.wdFormatDocument;//保存格式
object miss = System.Reflection.Missing.Value;
wordDoc.SaveAs(ref fileName, ref format, ref miss,
ref miss, ref miss, ref miss, ref miss,
ref miss, ref miss, ref miss, ref miss,
ref miss, ref miss, ref miss, ref miss,
ref miss);
//关闭wordDoc，wordApp对象
object SaveChanges = WdSaveOptions.wdSaveChanges;
object OriginalFormat = WdOriginalFormat.wdOriginalDocumentFormat;
object RouteDocument = false;
wordDoc.Close(ref SaveChanges, ref OriginalFormat, ref RouteDocument);
wordApp.Quit(ref SaveChanges, ref OriginalFormat, ref RouteDocument);
}

//在书签处插入值
public bool InsertValue(string bookmark, string value)
{
object bkObj = bookmark;
if (wordApp.ActiveDocument.Bookmarks.Exists(bookmark))
{
wordApp.ActiveDocument.Bookmarks.get_Item(ref bkObj).Select();
wordApp.Selection.TypeText(value);
return true;
}
return false;
}
//插入页眉
public void SetPageHeader(string context)
{
wordApp.ActiveWindow.ActivePane.View.SeekView = WdSeekView.wdSeekCurrentPageHeader;

wordApp.ActiveWindow.View.Type = WdViewType.wdOutlineView;

wordApp.ActiveWindow.View.SeekView = WdSeekView.wdSeekPrimaryHeader;

wordApp.ActiveWindow.ActivePane.Selection.InsertAfter(context);

wordApp.Selection.ParagraphFormat.Alignment

= WdParagraphAlignment.wdAlignParagraphCenter;

//跳出页眉设置
wordApp.ActiveWindow.View.SeekView = WdSeekView.wdSeekMainDocument;
}

// 杀掉winword.exe进程
public void killWinWordProcess()
{
System.Diagnostics.Process[] processes = System.Diagnostics.Process.GetProcessesByName("WINWORD");
foreach (System.Diagnostics.Process process in processes)
{
bool b = process.MainWindowTitle == "";
if (process.MainWindowTitle == "")
{
process.Kill();
}
}
}
}
}