如何在C＃Windows窗体应用程序中将图表保存为带有保存文件对话框的图像

Question

单击按钮时，我想将图表保存为带有保存文件对话框的图像。 我的应用程序类型是c＃Windows Forms Application。 这样用户就可以将图像文件保存在他/她希望的任何目录中。

Answer 1

我做了一个工作：

private void exportAsImagebtn_Click(object sender, EventArgs e)
{   
    SaveFileDialog saveFileDialog = new SaveFileDialog();
    saveFileDialog.Filter = "PNG Image|*.png|JPeg Image|*.jpg";
    saveFileDialog.Title = "Save Chart As Image File";
    saveFileDialog.FileName = "Sample.png";

    DialogResult result = saveFileDialog.ShowDialog();
    saveFileDialog.RestoreDirectory = true;

    if (result == DialogResult.OK && saveFileDialog.FileName != "")
    {
        try
        {
            if (saveFileDialog.CheckPathExists)
            {
                if (saveFileDialog.FilterIndex == 2)
                {
                    chart.SaveImage(saveFileDialog.FileName, ChartImageFormat.Jpeg);
                }
                else if (saveFileDialog.FilterIndex == 1)
                {
                    chart.SaveImage(saveFileDialog.FileName, ChartImageFormat.Png);
                }

            }
            else
            {
                MessageBox.Show("Given Path does not exist");
            }
        }
        catch(Exception ex){
            MessageBox.Show(ex.Message);
        }
    }     
}

Answer 2

或者像这样使用字典扩展文件：

try
{
    //Check if chart has at least one enabled series with points
    if (chart1.Series.Any(s => s.Enabled && s.Points.Count>0))
    {
        SaveFileDialog save = new SaveFileDialog();
        save.Filter = "Image Files|*.png;";
        save.Filter = "Bitmap Image (.bmp)|*.bmp|Gif Image (.gif)|*.gif|JPEG Image (.jpeg)|*.jpeg|Png Image (.png)|*.png|Tiff Image (.tiff)|*.tiff";
        save.Title = "Save Chart Image As file";
        save.DefaultExt = ".png";
        if (save.ShowDialog() == DialogResult.OK)
        {
            var imgFormats = new Dictionary<string, ChartImageFormat>()
            {
                {".bmp", ChartImageFormat.Bmp}, 
                {".gif", ChartImageFormat.Gif}, 
                {".jpg", ChartImageFormat.Jpeg}, 
                {".jpeg", ChartImageFormat.Jpeg}, 
                {".png", ChartImageFormat.Png}, 
                {".tiff", ChartImageFormat.Tiff}, 
            };
            var fileExt = System.IO.Path.GetExtension(save.FileName).ToString().ToLower();
            if (imgFormats.ContainsKey(fileExt))
            {
                chart1.SaveImage(save.FileName, imgFormats[fileExt]);
            }
            else
            { 
                throw new Exception(String.Format("Only image formats '{0}' supported", string.Join(", ", imgFormats.Keys)));
            }
        }
    }
    else
    {
        throw new Exception("Nothing to export");
    }
}
catch (Exception ex)
{
    MessageBox.Show("SaveChartAsImage()", ex.Message);
}