private bool IsWatermarkEnabled(IWatermarkConfiguration watermarkConfig, Uri requestUrl)
{
bool haveIgnoreWatermarkQueryString = requestUrl.Query.IndexOf("wm=false", StringComparison.OrdinalIgnoreCase) != -1;
return(!watermarkConfig.EnableIgnoreWatermarkQueryString ||
(watermarkConfig.EnableIgnoreWatermarkQueryString && !haveIgnoreWatermarkQueryString));
}
private void WriteWatermarkTextToImage(IWatermarkConfiguration config, Graphics graphic)
{
var watermarkFont = new Font("Arial", config.FontSize);
var brush = new SolidBrush(Color.FromArgb(80, Color.White));
SizeF textSize = graphic.MeasureString(config.WatermarkText, watermarkFont);
IEnumerable <PointF> positions = GetAllTextPositionByConfigFontAndImage(config, textSize, graphic);
foreach (PointF position in positions)
{
graphic.DrawString(config.WatermarkText, watermarkFont, brush, position);
}
}
private void ContextOnBeginRequest(object sender, EventArgs eventArgs)
{
var application = (HttpApplication)sender;
HttpContext context = application.Context;
if (context.Request.Url.PathAndQuery.Contains("ShowMedia.ashx"))
{
IWatermarkConfiguration watermarkConfig = GetWatermarkConfigOrDefault(context.Request.QueryString);
if (watermarkConfig != null && IsWatermarkEnabled(watermarkConfig, context.Request.Url))
{
var filter = new ResponseFilterStream(context.Response.Filter);
filter.TransformStream += AddWatermarkToStream;
context.Response.Filter = filter;
context.Items.Add(WatermarkConfigKey, watermarkConfig);
}
}
}
private IEnumerable <PointF> GetAllTextPositionByConfigFontAndImage(IWatermarkConfiguration config, SizeF watermarkSize, Graphics graphic)
{
if (config.ShowOnTopLeft)
{
yield return(new PointF(0, 0));
}
if (config.ShowOnTopRight)
{
yield return(new PointF(graphic.VisibleClipBounds.Width - watermarkSize.Width, 0));
}
if (config.ShowOnBottmRight)
{
yield return
(new PointF(graphic.VisibleClipBounds.Width - watermarkSize.Width,
graphic.VisibleClipBounds.Height - watermarkSize.Height));
}
if (config.ShowOnBottmLeft)
{
yield return(new PointF(0, graphic.VisibleClipBounds.Height - watermarkSize.Height));
}
}
private void WriteWatermarkImageToImage(IWatermarkConfiguration config, Graphics graphic)
{
IMediaFile originalMediaFile = MediaUrlHelper.GetFileFromQueryString(HttpContext.Current.Request.QueryString);
IMediaFile imageFile;
using (var conn = new DataConnection())
{
imageFile = conn.Get <IMediaFile>().SingleOrDefault(i => i.KeyPath == config.WatermarkImageFilePath);
}
Image watermarkImage = Image.FromStream(imageFile.GetReadStream());
IEnumerable <PointF> positions = GetAllTextPositionByConfigFontAndImage(config, watermarkImage.Size, graphic);
Size originalImageSize = GetImageSizeFromCacheOrFile(originalMediaFile);
float widthRatio = graphic.VisibleClipBounds.Width / originalImageSize.Width;
float heightRatio = graphic.VisibleClipBounds.Height / originalImageSize.Height;
var watermarkSize = new SizeF(watermarkImage.Width * widthRatio, watermarkImage.Height * heightRatio);
foreach (PointF position in positions)
{
graphic.DrawImage(watermarkImage, position.X, position.Y, watermarkSize.Width, watermarkSize.Height);
}
}
