Question

delphi 保存图片问题！！！

procedure TForm1.BitBtn2Click(Sender: TObject);
var
Bitmap : TImage;

begin

try
Bitmap.Picture.LoadFromFile(string(OpenPictureDialog1.FileName));

Bitmap.Picture.SaveToFile('C:\screen.jpg');//提示错在这句
Application.MessageBox('保存成功', '提示', MB_OK);
finally
Bitmap.Picture.Free;
end;
end;
=========================
出现如图错误，求助啊
procedure TForm1.BitBtn2Click(Sender: TObject);
var
Bitmap : TImage;
begin
try
Bitmap.Picture.LoadFromFile(string(OpenPictureDialog1.FileName));
Bitmap.Picture.SaveToFile('C:\screen.jpg');//提示错在这句
Application.MessageBox('保存成功', '提示', MB_OK);
finally
Bitmap.Picture.Free;
end;
end;
=========================
出现如图错误，求助啊

Answer 1

procedure TForm1.BitBtn2Click(Sender: TObject);
var
Bitmap : TImage;

begin

try
if OpenPictureDialog1.Execute then
begin
Bitmap:=TImage.Create(Self);
Bitmap.Picture.LoadFromFile(string(OpenPictureDialog1.FileName));
Bitmap.Picture.SaveToFile('C:\screen.jpg');//提示错在这句
Application.MessageBox('保存成功', '提示', MB_OK);
end;
finally
Bitmap.Free;
end;
end;

Answer 2

操作JPEG图片,应该引用JPEG单元,一错也;
Bitmap : TImage;
Bitmap 要先创建,后使用,你没有创建,如何使用,而且后面还有 Bitmap.Picture.Free;
这句也是错的, 应该是Bitmap.Free;

Answer 3

不能直接操作JPG文件的，他只认识BMP文件！