替换word模板中的字 相当于修改word内容了（保存了word原风格）

    //替换word模板中的字 相当于修改word内容了
    private void WordReplace(string filePath, string strOld, string strNew)
    {
        Microsoft.Office.Interop.Word._Application app = new Microsoft.Office.Interop.Word.ApplicationClass();
        object nullobj = System.Reflection.Missing.Value;
        object file = filePath;
        Microsoft.Office.Interop.Word._Document doc=app.Documents.Open(
        ref file, ref nullobj, ref nullobj,
        ref nullobj, ref nullobj, ref nullobj,
        ref nullobj, ref nullobj, ref nullobj,
        ref nullobj, ref nullobj, ref nullobj,
        ref nullobj, ref nullobj, ref nullobj, ref nullobj) as Microsoft.Office.Interop.Word._Document;

        app.Selection.Find.ClearFormatting();
        app.Selection.Find.Replacement.ClearFormatting();
        app.Selection.Find.Text = strOld;
        app.Selection.Find.Replacement.Text = strNew;

        object objReplace = Microsoft.Office.Interop.Word.WdReplace.wdReplaceAll;
        app.Selection.Find.Execute(ref nullobj, ref nullobj, ref nullobj,
                                   ref nullobj, ref nullobj, ref nullobj,
                                   ref nullobj, ref nullobj, ref nullobj,
                                   ref nullobj, ref objReplace, ref nullobj,
                                   ref nullobj, ref nullobj, ref nullobj);

        //格式化
        //doc.Content.AutoFormat();
        //清空Range对象
        //Microsoft.Office.Interop.Word.Range range = null;

        //保存
        doc.Save();

        //Microsoft.Office.Interop.Word.Range range = null;
        doc.Close(ref nullobj, ref nullobj, ref nullobj);

        app.Quit(ref nullobj, ref nullobj, ref nullobj);
    }