function ProgressBarform(max:integer):tProgressBar;
var
ProgressBar1:tProgressBar;
form:tform;
begin
application.CreateForm(tform,form);
form.Position:=poScreenCenter;
form.BorderStyle:=bsnone;
form.Height:=30;
form.Width:=260;
ProgressBar1:=tProgressBar.Create(form);
ProgressBar1.Smooth:=true;
ProgressBar1.Max:=max;
ProgressBar1.Parent:=form;
ProgressBar1.Height:=20;
ProgressBar1.Width:=250;
ProgressBar1.Left:=5;
ProgressBar1.Top:=5;
ProgressBar1.Step:=1;
form.Show;
result:=ProgressBar1;
end; 

function ExportToExcel(dbgrid:tdbgrid):boolean;
const
xlNormal=-4143;
var
i,j,k:integer;
str,filename:string;
excel:OleVariant;
SavePlace: TBookmark;
savedialog:tsavedialog;
ProgressBar1:TProgressBar;
begin
result:=false;
filename:='''';
if dbgrid.DataSource.DataSet.RecordCount>65536 then
begin
if application.messagebox(''需要导出的数据过大，Excel最大只能容纳65536行,是否还要继续？'',''询问'',mb_yesno+mb_iconquestion)=idno then
exit;
end;
screen.Cursor:=crHourGlass;
try
excel:=CreateOleObject(''Excel.Application'');
excel.workbooks.add;
except
screen.cursor:=crDefault;
showmessage(''无法调用Excel！'');
exit;
end;
savedialog:=tsavedialog.Create(nil);
savedialog.Filter:=''Excel文件(*.xls)|*.xls'';
if savedialog.Execute then
begin
if FileExists(savedialog.FileName) then
try
if application.messagebox(''该文件已经存在，要覆盖吗？'',''询问'',mb_yesno+mb_iconquestion)=idyes then
DeleteFile(PChar(savedialog.FileName))
else
begin
Excel.Quit;
savedialog.free;
screen.cursor:=crDefault;
Exit;
end;
except
Excel.Quit;
savedialog.free;
screen.cursor:=crDefault;
Exit;
end;
filename:=savedialog.FileName;
end;
savedialog.free;
if filename='''' then
begin
result:=true;
Excel.Quit;
screen.cursor:=crDefault;
exit;
end;
k:=0;
for i:=0 to dbgrid.Columns.count-1 do
begin
if dbgrid.Columns.Items[i].Visible then
begin
//Excel.Columns[k+1].ColumnWidth:=dbgrid.Columns.Items[i].Title.Column.Width;
excel.cells[1,k+1]:=dbgrid.Columns.Items[i].Title.Caption;
inc(k);
end;
end;

dbgrid.DataSource.DataSet.DisableControls;
saveplace:=dbgrid.DataSource.DataSet.GetBookmark;
dbgrid.DataSource.dataset.First;
i:=2;
if dbgrid.DataSource.DataSet.recordcount>65536 then
ProgressBar1:=ProgressBarform(65536)
else
ProgressBar1:=ProgressBarform(dbgrid.DataSource.DataSet.recordcount);
while not dbgrid.DataSource.dataset.Eof do
begin
k:=0;
for j:=0 to dbgrid.Columns.count-1 do
begin
if dbgrid.Columns.Items[j].Visible then
begin
excel.cells[i,k+1].NumberFormat:=''@'';
if not dbgrid.DataSource.dataset.fieldbyname(dbgrid.Columns.Items[j].FieldName).isnull then
begin
str:=dbgrid.DataSource.dataset.fieldbyname(dbgrid.Columns.Items[j].FieldName).value;
Excel.Cells[i, k + 1] := Str;
end;
inc(k);
end
else
continue;
end;
if i=65536 then
break;
inc(i);
ProgressBar1.StepBy(1);
dbgrid.DataSource.dataset.next;
end;
progressbar1.Parent.Free;

dbgrid.DataSource.dataset.GotoBookmark(SavePlace);
dbgrid.DataSource.dataset.EnableControls;

try
if copy(FileName,length(FileName)-3,4)<>''.xls'' then
FileName:=FileNam