saveFileDialog1.Title = "保存";             saveFileDialog1.Filter = "*.png|*.png";             saveFileDialog1.RestoreDirectory = true;             if (saveFileDialog1.ShowDialog() == DialogResult.OK)             {                 timer1.Enabled = true;             }

timer1.Enabled = false;             Bitmap bit = new Bitmap(this.Width, this.Height);//实例化一个和窗体一样大的bitmap             Graphics g = Graphics.FromImage(bit);             g.CompositingQuality = CompositingQuality.HighQuality;//质量设为最高             //g.CopyFromScreen(this.Left, this.Top, 0, 0, new Size(this.Width, this.Height));//保存整个窗体为图片             g.CopyFromScreen(chartType.PointToScreen(Point.Empty), Point.Empty, chartType.Size);//只保存某个控件             bit.Save(saveFileDialog1.FileName);//默认保存格式为PNG，保存成jpg格式质量不是很好             if (File.Exists(saveFileDialog1.FileName.ToString()))             {                 MessageBox.Show("截图成功！");                 return;             }