txtdate=DateTime.Parse(Context.Request["txtDate"].ToString()).ToString("yyyy-MM-dd");





//类调用：
string cOnnectionString= ConfigurationManager.ConnectionStrings["DefaultDbServerConnection"].ConnectionString;



sql语句按日期查询
select * from History where convert(varchar(10),STime,120)='2011-12-01'
select * from History where datediff(dd,STime,'2011-12-01')=0
select * from History where STime>='2011-12-1 00:00:00.000' and STime<='2011-12-1 23:59:59.997'




 //最近新接触可空类型，工作中写了这么一个对象类，其中有一个属性字段是这样子的
     /// 

        /// 取样日期时间
        /// 

        private DateTime? samdate;
       public DateTime? SamDate
       {
           get { return samdate; }
           set { samdate = value; }
 
       }

//最终在UI层赋值后，显示时，一直不出现，最终原因原来是
//DateTime?为可空，如果不空，得先转换为string，然后将string转换为DateTime，在将DateTime转换为你想要的格式的string串，
//感觉非常麻烦，具体方法如下
 string strdate = DateTime.Parse(modSamVouch.SamDate.ToString()).ToString("yyyy-MM-dd")
//亦或者我的方法
string strdate=SamDate==null?""：DateTime.Parse（SamDate）.ToString("yyyy-MM-dd")





Aspose.Cells.dll使用：


 public static DataTable ExeclToDataTable(string Path)
        {
            try
            {
                DataTable dt = new DataTable();
                Aspose.Cells.Workbook workbook = new Workbook();
                workbook.Open(Path);
                Worksheets wsts = workbook.Worksheets;
                for (int i = 0; i                 {
                    Worksheet wst = wsts[i];
                    int MaxR = wst.Cells.MaxRow;
                    int MaxC = wst.Cells.MaxColumn;
                    if (MaxR > 0 && MaxC > 0)
                    {
                        dt = wst.Cells.ExportDataTableAsString(0, 0, MaxR + 1, MaxC + 1, true);
                    }
                }
                return dt;
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }




在SQLSERVER中批量替换字符串的方法:


update ProgInfo set JoinTime=replace(JoinTime,'2007-3-2','2007-03-02')