//简单使用的水印类.
public class WaterMark
{
private bool _textMark = false;
private bool _imgMark = false;
private string _text = "";
private string _imgPath = "";
private int _markX = 0;
private int _markY = 0;
private float _transparency = 1;
private string _fontFamily = "宋体";
private Color _textColor = Color.Black;
private bool _textbold = false;
int[] sizes = new int[] { 48, 32, 16, 8, 6, 4 };
/// <summary>
/// 实例化一个水印类
/// </summary>
public WaterMark()
{
}
/// <summary>
/// 初始化一个只添加文字水印得实例
/// </summary>
/// <param name="text">水印文字</param>
/// <param name="fontFamily">文字字体</param>
/// <param name="bold">是否粗体</param>
/// <param name="color">字体颜色</param>
/// <param name="markX">标记位置横坐标</param>
/// <param name="markY">标记位置纵坐标</param>
public WaterMark(string text, string fontFamily, bool bold, Color color, int markX, int markY)
{
this._imgMark = false;
this._textMark = true;
this._text = text;
this._fontFamily = fontFamily;
this._textbold = bold;
this._textColor = color;
this._markX = markX;
this._markY = MarkY;
}
/// <summary>
/// 实例化一个只添加图片水印得实例
/// </summary>
/// <param name="imagePath">水印图片路径</param>
/// <param name="tranparence">透明度</param>
/// <param name="markX">标记位置横坐标</param>
/// <param name="markY">标记位置纵坐标</param>
public WaterMark(string imagePath, float tranparence, int markX, int markY)
{
this._textMark = false;
this._imgMark = true;
this._imgPath = imagePath;
this._markX = markX;
this._markY = MarkY;
this._transparency = tranparence;
}
/// <summary>
/// 是否添加文字水印
/// </summary>
public bool TextMark
{
get { return _textMark; }
set { _textMark = value; }
}
/// <summary>
/// 是否添加图片水印
/// </summary>
public bool ImageMark
{
get { return _imgMark; }
set { _imgMark = value; }
}
/// <summary>
/// 文字水印得内容
/// </summary>
public string Text
{
get { return _text; }
set { _text = value; }
}
/// <summary>
/// 图片水印得图片地址
/// </summary>
public string ImagePath
{
get { return _imgPath; }
set { _imgPath = value; }
}
/// <summary>
/// 添加水印位置得横坐标
/// </summary>
public int MarkX
{
get { return _markX; }
set { _markX = value; }
}
/// <summary>
/// 添加水印位置得纵坐标
/// </summary>
public int MarkY
{
get { return _markY; }
set { _markY = value; }
}
/// <summary>
/// 水印得透明度
/// </summary>
public float Transparency
{
get
{
if (_transparency > 1.0f)
{
_transparency = 1.0f;
}
return _transparency;
}
set { _transparency = value; }
}
/// <summary>
/// 水印文字得颜色
/// </summary>
public Color TextColor
{
get { return _textColor; }
set { _textColor = value; }
}
/// <summary>
/// 水印文字得字体
/// </summary>
public string TextFontFamily
{
get { return _fontFamily; }
set { _fontFamily = value; }
}
/// <summary>
/// 水印文字是否加粗
/// </summary>
public bool Bold
{
get { return _textbold; }
set { _textbold = value; }
}
/// <summary>
/// 添加水印，此方法适用于gif格式得图片
/// </summary>
/// <param name="image">需要添加水印得图片</param>
/// <returns>添加水印之后得图片</returns>
public Image Mark(Image img)
{
try
{
//添加文字水印
if (this.TextMark)
{
//根据源图片生成新的Bitmap对象作为作图区，为了给gif图片添加水印，才有此周折
Bitmap newBitmap = new Bitmap(img.Width, img.Height, PixelFormat.Format24bppRgb);
//设置新建位图得分辨率
newBitmap.SetResolution(img.HorizontalResolution, img.VerticalResolution);
//创建Graphics对象，以对该位图进行操作
Graphics g = Graphics.FromImage(newBitmap);
//消除锯齿
g.SmoothingMode = SmoothingMode.AntiAlias;
//将原图拷贝到作图区
g.DrawImage(img, new Rectangle(0, 0, img.Width, img.Height), 0, 0, img.Width, img.Height, GraphicsUnit.Pixel);
//声明字体对象
Font cFont = null;
//用来测试水印文本长度得尺子
SizeF size = new SizeF();
//探测出一个适合图片大小得字体大小，以适应水印文字大小得自适应
for (int i = 0; i < 6; i++)
{
//创建一个字体对象
cFont = new Font(this.TextFontFamily, sizes[i]);
//是否加粗
if (!this.Bold)
{
cFont = new Font(this.TextFontFamily, sizes[i], FontStyle.Regular);
}
else
{
cFont = new Font(this.TextFontFamily, sizes[i], FontStyle.Bold);
}
//测量文本大小
size = g.MeasureString(this.Text, cFont);
//匹配第一个符合要求得字体大小
if ((ushort)size.Width < (ushort)img.Width)
{
break;
}
}
//创建刷子对象，准备给图片写上文字
Brush brush = new SolidBrush(this.TextColor);
//在指定得位置写上文字
g.DrawString(this.Text, cFont, brush, this.MarkX, this.MarkY);
//释放Graphics对象
g.Dispose();
//将生成得图片读入MemoryStream
System.IO.MemoryStream ms = new System.IO.MemoryStream();
newBitmap.Save(ms, ImageFormat.Jpeg);
//重新生成Image对象
img = System.Drawing.Image.FromStream(ms);
//返回新的Image对象
return img;
}
//添加图像水印
if (this.ImageMark)
{
//获得水印图像
Image markImg = Image.FromFile(this.ImagePath);
//创建颜色矩阵
float[][] ptsArray ={
new float[] {1, 0, 0, 0, 0},
new float[] {0, 1, 0, 0, 0},
new float[] {0, 0, 1, 0, 0},
new float[] {0, 0, 0, this.Transparency, 0}, //注意：此处为0.0f为完全透明，1.0f为完全不透明
new float[] {0, 0, 0, 0, 1}};
ColorMatrix colorMatrix = new ColorMatrix(ptsArray);
//新建一个Image属性
ImageAttributes imageAttributes = new ImageAttributes();
//将颜色矩阵添加到属性
imageAttributes.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default,
ColorAdjustType.Default);
//生成位图作图区
Bitmap newBitmap = new Bitmap(img.Width, img.Height, PixelFormat.Format24bppRgb);
//设置分辨率
newBitmap.SetResolution(img.HorizontalResolution, img.VerticalResolution);
//创建Graphics
Graphics g = Graphics.FromImage(newBitmap);
//消除锯齿
g.SmoothingMode = SmoothingMode.AntiAlias;
//拷贝原图到作图区
g.DrawImage(img, new Rectangle(0, 0, img.Width, img.Height), 0, 0, img.Width, img.Height, GraphicsUnit.Pixel);
//如果原图过小
if (markImg.Width > img.Width || markImg.Height > img.Height)
{
System.Drawing.Image.GetThumbnailImageAbort callb = null;
//对水印图片生成缩略图,缩小到原图得1/4
System.Drawing.Image new_img = markImg.GetThumbnailImage(img.Width / 4, markImg.Height * img.Width / markImg.Width, callb, new System.IntPtr());
//添加水印
g.DrawImage(new_img, new Rectangle(this.MarkX, this.MarkY, new_img.Width, new_img.Height), 0, 0, new_img.Width, new_img.Height, GraphicsUnit.Pixel, imageAttributes);
//释放缩略图
new_img.Dispose();
//释放Graphics
g.Dispose();
//将生成得图片读入MemoryStream
System.IO.MemoryStream ms = new System.IO.MemoryStream();
newBitmap.Save(ms, ImageFormat.Jpeg);
//返回新的Image对象
img = Image.FromStream(ms);
return img;
}
//原图足够大
else
{
//添加水印
g.DrawImage(markImg, new Rectangle(this.MarkX, this.MarkY, markImg.Width, markImg.Height), 0, 0, markImg.Width, markImg.Height, GraphicsUnit.Pixel, imageAttributes);
//释放Graphics
g.Dispose();
//将生成得图片读入MemoryStream
System.IO.MemoryStream ms = new System.IO.MemoryStream();
newBitmap.Save(ms, ImageFormat.Jpeg);
//返回新的Image对象
img = Image.FromStream(ms);
return img;
}
}
return img;
}
catch
{
return img;
}
}
}
