NPOI_2.1.3_学习记录(1)-创建Excel的详细信息，如：作者、标题、标记、备注、主题等。

static void Main(string[] args)
        {
            //Create 一个Excel对象
            HSSFWorkbook hssfWorkbook = new HSSFWorkbook();
            //Create Excel的属性中的来源以及说明等
            DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
            dsi.Company = "NPOI-1";
            dsi.Category = "NPOI-2";
            dsi.Manager = "NPOI-3";
            //创建好的对象赋给hssfWorkbook,这样才能保证这些信息被写入文件
            hssfWorkbook.DocumentSummaryInformation = dsi;
            SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
            si.Subject = "NPOI SDK Example 1";
            si.Title = "NPOI SDK Example 2";
            si.ApplicationName = "NPOI SDK Example 3";
            si.Author = "NPOI SDK Example 4";
            si.LastAuthor = "NPOI SDK Example 5";
            si.Comments = "NPOI SDK Example 6";
            si.CreateDateTime = DateTime.Now.AddMonths(-2);
            //创建好的对象赋给hssfWorkbook,这样才能保证这些信息被写入文件
            hssfWorkbook.SummaryInformation = si;

            //创建文件并写入
            FileStream file = new FileStream(@"demo.xls", FileMode.Create);
            hssfWorkbook.Write(file);
            file.Close();
        }