Time Range: this week, this month, and this year

                   Case   "  Within this week  " :
Datetime retstartday = datetime. Now. Date. adddays (-( Int ) (Datetime. Now. dayofweek) + 1 );
Datetime retendday = datetime. Now. Date. adddays ( 7 -( Int ) (Datetime. Now. dayofweek). adddays ( 1 );
Sbsqldate. append ( " Joindate> ='  " + Retstartday + "  'And joindate <='  " + Retendday + "  '  " );
 Break ;
 Case   "  Within this month  " :
Datetime monthstart =New Datetime (datetime. Now. Year, datetime. Now. Month, 1 );
Datetime monthend = New Datetime (datetime. Now. Year, datetime. Now. Month + 1 , 1 ). Adddays (- 1 );
Sbsqldate. append ( "  Joindate> ='  " + Monthstart + "  'And joindate <=' " + Monthend + "  '  " );
 Break ;
 Case   "  Within this year  " :
Datetime yearstart = New Datetime (datetime. Now. Date. Year, 1 , 1 );
Datetime yearend =New Datetime (datetime. Now. Date. Year + 1 , 1 , 1 ). Adddays (- 1 );
Sbsqldate. append ( "  Joindate> ='  " + Yearstart + "  'And joindate <='  " + Yearend + "  ' " );
 Break ;

List <radio> radlist = radgrop. checkeditems;
 Foreach (Radio item In Radlist)
{
 Switch (Item. boxlabel)
{
 Case   "  Do not remember  " :
 Break ;
Case   "  Yesterday  " : Sbsqldate. append ( "  Createdate> ='  " + New Datetime (datetime. Now. Year, datetime. Now. Month, datetime. Now. Day). adddays (- 1 ) + "  And createdate <'  " + New Datetime (datetime. Now. Year, datetime. Now. Month, datetime. Now. Day) +"  '  " );
 Break ;
 Case   "  Today  " : Sbsqldate. append ( "  Createdate ='  " + Datetime. Now. Date + "  '  " );
 Break ;
 Case   "  Past 7 days  " : Sbsqldate. append ( "  Createdate> ='  " + Datetime. Now. adddays (- 7 ) + "  And createdate <='  " + Datetime. now + "  '  " );
Break ;
 Case   "  Past 30 days  " : Sbsqldate. append ( "  Createdate> ='  " + Datetime. Now. adddays (- 30 ) + "  And createdate <='  " + Datetime. now + "  '  " );
 Break ;
 Case   "  Within this week  " :
Datetime retstartday = datetime. Now. Date. adddays (-( Int ) (Datetime. Now. dayofweek) + 1 );
Datetime retendday = datetime. Now. Date. adddays ( 7 -( Int ) (Datetime. Now. dayofweek). adddays ( 1 );
Sbsqldate. append ( "  Createdate> ='  " + Retstartday + "  And createdate <='  " + Retendday + "  '  " );
 Break ;
 Case   "  Within this month  " :
Datetime monthstart = New Datetime (datetime. Now. Year, datetime. Now. Month, 1 );
Datetime monthend = New Datetime (datetime. Now. Year, datetime. Now. Month + 1 , 1 ). Adddays (- 1 );
Sbsqldate. append ( "  Createdate> ='  " + Monthstart + " And createdate <='  " + Monthend + "  '  " );
 Break ;
 Case   "  Within this year  " :
Datetime yearstart = New Datetime (datetime. Now. Date. Year, 1 , 1 );
Datetime yearend = New Datetime (datetime. Now. Date. Year + 1 , 1 , 1 ). Adddays (- 1 );
Sbsqldate. append ( "  Createdate> ='  " + Yearstart + "  And createdate <='  " + Yearend + " '  " );
 Break ;
 Case   "  Specified Date  " : Sbsqldate. append ( "  Createdate> ='  " + Dfstatedate. Text. Trim () + "  And createdate <='  " + (Dfenddate. Text. Trim () = " 0001-1-1 0:00:00  " ? Datetime. Now. tostring (): dfenddate. Text. Trim () + "  '  " );
 Break ;
}
}