一个过程，直接调用就可以了！

procedure ChangeDbGridColColor(ojbDbGrid:TDbGrid);
var
  i:integer;
begin
     for i:= 0 to ojbDbGrid.Columns.Count -1 do
   begin
      case i mod 3 of
      0: ojbDbGrid.Columns.Items[i].Color:=TColor($0023AF82);
      1: ojbDbGrid.Columns.Items[i].Color:=TColor($00339CDB);
      2: ojbDbGrid.Columns.Items[i].Color:=TColor($00C69C6D);
      end;
   end;
end;

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