HasRows属性CSDN上明明写着“指示datareader是否包含一行或多行”,,可是,这个属性有时候从库中查出没有一行,他仍然为TRUE,有时候就不会。。跟踪了好几次!!!同志们,你们有没有发现这种情况?????
CSQLConn aConn = new CSQLConn();
sql = "select Min(M_Date) as Mi_Day from " + tbName + " where PZ='" + DM + "'";
using (SqlDataReader dr_Day = aConn.GetReader(sql))
{
if (dr_Day.HasRows)
{
if (dr_Day.Read())
Day = dr_Day["Mi_Day"].ToString();
}
else
Day = "";
dr_Day.Close();
}
CSQLConn aConn = new CSQLConn();
sql = "select Min(M_Date) as Mi_Day from " + tbName + " where PZ='" + DM + "'";
using (SqlDataReader dr_Day = aConn.GetReader(sql))
{
if (dr_Day.HasRows)
{
if (dr_Day.Read())
Day = dr_Day["Mi_Day"].ToString();
}
else
Day = "";
dr_Day.Close();
}
所以值总是为true。