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syziy 发表于 2008-10-4 21:38

生成缩略图的放法(直接复制就能用了)

[code]public void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)&e/TE9d*B)F(m.f&U
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System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath);
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int towidth = width;
%j? n{N1db int toheight = height;
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cUAeY*Y int x = 0;&Dz\[4T1Pj-[
int y = 0;
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y int ow = originalImage.Width;qyf wf
int oh = originalImage.Height; U0I$v4v&n8B&Z
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switch (mode)iK"[ `4B%\
{
tWZ[5Io } CIQ,B case "HW"://指定高宽缩放（可能变形） K] ?qwf
break;
W-HFz(~t%E case "W"://指定宽，高按比例
1R[vsD.k,u~:[h toheight = originalImage.Height * width / originalImage.Width;U7X+IB3u)o
break;
,a,n^#n.y:Y^'^v case "H"://指定高，宽按比例5k&q@Q)X}:PIJ1Y
towidth = originalImage.Width * height / originalImage.Height;
R-}3H(T%IP break;
2c7MaQU/|W3r?)S3c case "Cut"://指定高宽裁减（不变形）
2S[ b"{"HG if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight):FG^b-wn
{
Z9A4Jo6_R7^%K oh = originalImage.Height;x9R&r4y-?gT
ow = originalImage.Height * towidth / toheight;
.aG}_1FnjY y = 0;*|0v4V(` o
x = (originalImage.Width - ow) / 2;
3} `9Ml3B }
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{
t8w#_,AswskB ow = originalImage.Width;
}H$E#F2z'@+f9~&K4@;@ oh = originalImage.Width * height / towidth;
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y = (originalImage.Height - oh) / 2;f6@ZA e%U'Q ~
}
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default:
&{~C4cNI break;
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R!x/~J Y //新建一个bmp图片r6x5bk S#r#H9wJ
System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight); B?|.~_5l_3g

(Tq3sQ5N.o //新建一个画板%]-F7T$?$M v]z9h;u@T
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap);*pp c*JB'jp+h}
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//设置高质量插值法 sqm2?"m],FJ
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
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+o0\pm4lk$v~ //设置高质量,低速度呈现平滑程度
*rx-z |5or6yX wQ g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;'Iu;f:s*I7T
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//清空画布并以透明背景色填充

W_V)T|{k g.Clear(System.Drawing.Color.Transparent);s \#ol ]

^RlaP //在指定位置并且按指定大小绘制原图片的指定部分
cr"EM4~~KP g.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, towidth, toheight),
;HCZzP new System.Drawing.Rectangle(x, y, ow, oh),B7b:?2]_K1x&^
System.Drawing.GraphicsUnit.Pixel);d,jb(v&zOq$K
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try
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//以jpg格式保存缩略图xzQi+i
bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);'qXnd+R#|N
}
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mEZ catch (System.Exception e)
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throw e;
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p-{p&bY6Xe4O finally'ai6GJYxZ_A/D3c
{
*j @p*\^ originalImage.Dispose();
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g.Dispose();
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}[/code]

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