using system;

using system.data;

using system.configuration;

using system.web;

using system.web.security;

using system.web.ui;

using system.web.ui.webcontrols;

using system.web.ui.webcontrols.webparts;

using system.web.ui.htmlcontrols;

using system.io;

using system.drawing;

using system.drawing.imaging;

///

/// 圖片處理類

/// 1、生成縮略圖片或按照比例改變圖片的大小和畫質

/// 2、將生成的縮略圖放到指定的目錄下

///

public class imageclass

{

public system.drawing.image resourceimage;

private int imagewidth;

private int imageheight;

public string errmessage;

///

/// 類的構造函數(shù)

///

/// 圖片文件的全路徑名稱

public imageclass(string imagefilename)

{

resourceimage = system.drawing.image.fromfile(imagefilename);

errmessage = ;

}

public bool thumbnailcallback()

{

return false;

}

///

/// 生成縮略圖重載方法1，返回縮略圖的image對象

///

/// 縮略圖的寬度

/// 縮略圖的高度

/// 縮略圖的image對象

public system.drawing.image getreducedimage(int width, int height)

{

try

{

system.drawing.image reducedimage;

system.drawing.image.getthumbnailimageabort callb = new system.drawing.image.getthumbnailimageabort(thumbnailcallback);

reducedimage = resourceimage.getthumbnailimage(width, height, callb, intptr.zero);

return reducedimage;

}

catch (exception e)

{

errmessage = e.message;

return null;

}

}

///

/// 生成縮略圖重載方法2，將縮略圖文件保存到指定的路徑

///

/// 縮略圖的寬度

/// 縮略圖的高度

/// 縮略圖保存的全文件名，(帶路徑)，參數(shù)格式：d:images ilename.jpg

/// 成功返回true，否則返回false

public bool getreducedimage(int width, int height, string targetfilepath)

{

try

{

system.drawing.image reducedimage;

system.drawing.image.getthumbnailimageabort callb = new system.drawing.image.getthumbnailimageabort(thumbnailcallback);

reducedimage = resourceimage.getthumbnailimage(width, height, callb, intptr.zero);

reducedimage.save(@targetfilepath, imageformat.jpeg);

reducedimage.dispose();

return true;

}

catch (exception e)

{

errmessage = e.message;

return false;

}

}

///

/// 生成縮略圖重載方法3，返回縮略圖的image對象

///

/// 縮略圖的寬度百分比 如：需要百分之80，就填0.8

/// 縮略圖的image對象

public system.drawing.image getreducedimage(double percent)

{

try

{

system.drawing.image reducedimage;

system.drawing.image.getthumbnailimageabort callb = new system.drawing.image.getthumbnailimageabort(thumbnailcallback);

imagewidth = convert.toint32(resourceimage.width * percent);

imageheight = convert.toint32(resourceimage.width * percent);

reducedimage = resourceimage.getthumbnailimage(imagewidth, imageheight, callb, intptr.zero);

return reducedimage;

}

catch (exception e)

{

errmessage = e.message;

return null;

}

}

///

/// 生成縮略圖重載方法4，返回縮略圖的image對象

///

/// 縮略圖的寬度百分比 如：需要百分之80，就填0.8

/// 縮略圖保存的全文件名，(帶路徑)，參數(shù)格式：d:images ilename.jpg

/// 成功返回true,否則返回false

public bool getreducedimage(double percent, string targetfilepath)

{

try

{

system.drawing.image reducedimage;

system.drawing.image.getthumbnailimageabort callb = new system.drawing.image.getthumbnailimageabort(thumbnailcallback);

imagewidth = convert.toint32(resourceimage.width * percent);

imageheight = convert.toint32(resourceimage.width * percent);

reducedimage = resourceimage.getthumbnailimage(imagewidth, imageheight, callb, intptr.zero);

reducedimage.save(@targetfilepath, imageformat.jpeg);

reducedimage.dispose();

return true;

}

catch (exception e)

{

errmessage = e.message;

return false;

}

}

}

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