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我在想在动态库里面完成写EXCEL的动做，现在不知道为什么报Invalid pointer operation.
现在是代码
uses
ShareMem,SysUtils,Classes,DBTables,Variants,ComObj;

{$R *.res}
procedure CopyDbDataToExcel(Const lQry:TQuery);
var
iCount, jCount: Integer;
XLApp: Variant;
Sheet: Variant;
Range : variant;
filename : String;
lQry1 : TQuery;
begin
lQry1 := lQry;
if not VarIsEmpty(XLApp) then
begin
XLApp.DisplayAlerts := False;
XLApp.Quit;
VarClear(XLApp);
end;
filename := 'F:\aaa.xls';
try
XLApp := CreateOleObject('Excel.Application');
except
Exit;
end;

XLApp.WorkBooks.Add;
XLApp.SheetsInNewWorkbook := 1;

XLApp.WorkBooks[1].WorkSheets[1].Name := '4443';
Sheet := XLApp.Workbooks[1].WorkSheets['4443'];
if not lQry1.Active then
begin
lQry1.Open;
Exit;
end;

lQry.first;
// for iCount := 0 to lQry.FieldCount - 1 do
// Sheet.Cells[1, iCount + 1] :=lQry. ;

jCount := 1;
try
while not lQry1.Eof do
begin
for iCount := 0 to lQry.FieldCount - 1 do
begin
Sheet.Cells[jCount + 1, iCount + 1] :=lQry1.Fields[iCount].AsString ;
if lQry1.Fields[iCount].AsString='是' then
begin
Range := Sheet.Cells[jCount + 1, iCount + 1];
Range.Interior.ColorIndex:=39;
end;
end;
Inc(jCount);
lQry1.Next;
end;
// Sheet:= unassigned;
// Range.Quit;
// Range := unassigned;
XlApp.Visible := True;
// XLApp.WorkBooks[1].saveas(filename);
// XLApp.Workbooks[1].close;
// XLApp.quit;
// XLApp:=unassigned;
// Sheet.quit;
Except
end;
end;