水印图像

Question

不拉丝我想出了一个错误：Solution for "A Graphics Object cannot be Created from an Image that has an Indexed Pixel Format"

但是： Graphics对象不能从一个具有索引像素格式

所以我实现了这个代码到我的方法的形像造现在我的水印不想绘制在我的图像上。

请任何人都可以协助。

代码：

private Image AddWaterMark(Image original) 
{ 
    Image waterMark = Image.FromFile(ConfigurationManager.AppSettings["GalleryFolder"] + @"\watermark.png"); 
    Bitmap bm = (Bitmap)original; 

    Size waterMarkResize = ResizeFit(new Size(original.Width, original.Height)); 

    using (Image watermarkImage = new Bitmap(waterMark, waterMarkResize)) 
    using (Graphics imageGraphics = Graphics.FromImage(new Bitmap(bm.Width, bm.Height))) 
    { 
     imageGraphics.DrawImage(bm, new Rectangle(0, 0, bm.Width, bm.Height), 0, 0, bm.Width, bm.Height, GraphicsUnit.Pixel); 
     using (TextureBrush watermarkBrush = new TextureBrush(watermarkImage)) 
     { 
      int x = (original.Width/2 - watermarkImage.Width/2); 
      int y = (original.Height/2 - watermarkImage.Height/2); 
      watermarkBrush.TranslateTransform(x, y); 
      imageGraphics.FillRectangle(watermarkBrush, new Rectangle(new Point(x, y), new Size(watermarkImage.Width + 1, watermarkImage.Height))); 
     } 
    } 

    return bm; 
} 

Answer 1

你正在创建一个新的Bitmap传递给Graphics.FromImage后恢复原uneditted Bitmap。独立创建新的Bitmap，将其传递给FromImage，然后返回新的Bitmap。

var edit = new Bitmap(bm.Width, bm.Height); 
// ... 
using (Graphics imagesGraphics = Graphics.FromImage(edit)) 
{ 
    // draw original 
    // draw watermark 
} 
return edit;