Loop binding and loop deletion under arraylist

1: bind the drop-down menu
Arraylist IDs = new arraylist ();
Dataaccess. adminaccess login = new dataaccess. adminaccess (system. configuration. configurationmanager. deleettings ["connstring"]. tostring ());
Data. admindata dsuserinfo = login. Query ();
This. dropdownlist1.items. Clear ();
For (INT I = 0; I <dsuserinfo. Tables [0]. Rows. Count; I ++)
{

String id_str = dsuserinfo. Tables [0]. Rows [I] ["aid"]. tostring ();
IDs. Add (id_str );

}
Ienumerator ienum = IDs. getenumerator ();
While (ienum. movenext ())
{
This. dropdownlist1.items. Add (New listitem (ienum. Current. tostring (), "1 "));
}

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2: delete cyclically

Arraylist IDs = new arraylist ();
For (INT I = 0; I <this. gridview1.rows. Count; I ++)
{
Checkbox chk = (checkbox) gridview1.rows [I]. findcontrol ("checkall ");
If (chk. Checked)
{
String id_str = This. gridview1.datakeys [I]. value. tostring ();
Guid id = new GUID (id_str );
IDs. Add (ID );
}
}
Ienumerator ienum = IDs. getenumerator ();
While (ienum. movenext ())
{
Deleteid (guid) ienum. Current); // execute the delete function
}
Showall ();