C # class for generating image thumbnails

There are four overload methods in it, some that directly return the image object, some that generate thumbnails, and save them to the specified directory!

Using system. IO;
Using system. drawing;
Using system. Drawing. imaging;

/// <Summary>
/// Image Processing
/// 1. Generate a thumbnail or change the image size and image quality in proportion.
/// 2. Place the generated thumbnail in the specified directory.
/// </Summary>
Public class imageclass
{
Public Image resourceimage;
Private int imagewidth;
Private int imageheight;

Public String errmessage;

/// <Summary>
/// Constructor of the class
/// </Summary>
/// <Param name = "imagefilename"> full path name of the image file </param>
Public imageclass (string imagefilename)
{
Resourceimage = image. fromfile (imagefilename );
Errmessage = "";
}

Public bool thumbnailcallback ()
{
Return false;
}

/// <Summary>
/// Method 1 for generating thumbnail overloading. The image object of the thumbnail is returned.
/// </Summary>
/// <Param name = "width"> width of the thumbnail </param>
/// <Param name = "height"> height of the thumbnail </param>
/// <Returns> thumbnail image object </returns>
Public Image getreducedimage (INT width, int height)
{
Try
{
Image cecedimage;

image. getthumbnailimageabort callb = new image. getthumbnailimageabort (thumbnailcallback);
performancedimage = resourceimage. getthumbnailimage (width, height, callb, intptr. zero);
return reducedimage;
}< br> catch (exception e)
{< br> errmessage = E. message;
return NULL;
}< BR >}

///

// method 2 for generating thumbnail Overloading, save the thumbnail file to the specified path
///
/// width of the thumbnail
/// height of the thumbnail
/// the full file name saved by the thumbnail, (With path), parameter format: D: \ images \ filename.jpg
// success returns true, otherwise, false is returned.
Public bool getreducedimage (INT width, int height, string targetfilepath)
{< br> try
{< br> image performancedimage;

Image. getthumbnailimageabort callb = new image. getthumbnailimageabort (thumbnailcallback );

Performancedimage = resourceimage. getthumbnailimage (width, height, callb, intptr. Zero );
Performancedimage. Save (@ targetfilepath, imageformat. JPEG );

Cecedimage. Dispose ();

Return true;
}
Catch (exception E)
{
Errmessage = E. message;
Return false;
}
}

/// <Summary>
/// Method 3 for generating thumbnail overloading. The image object of the thumbnail is returned.
/// </Summary>
/// <Param name = "percent"> set the width percentage of the thumbnail to 0.8 if the width percentage is 80. </param>
/// <Returns> thumbnail image object </returns>
Public Image getreducedimage (double percent)
{
Try
{
Image cecedimage;

Image. getthumbnailimageabort callb = new image. getthumbnailimageabort (thumbnailcallback );

imagewidth = convert. toint32 (resourceimage. width * percent);
imageheight = convert. toint32 (resourceimage. width * percent);
performancedimage = resourceimage. getthumbnailimage (imagewidth, imageheight, callb, intptr. zero);
return reducedimage;
}< br> catch (exception e)
{< br> errmessage = E. message;
return NULL;
}< BR >}

/// <Summary>
/// Method 4 for generating thumbnail overloading. The image object of the thumbnail is returned.
/// </Summary>
/// <Param name = "percent"> set the width percentage of the thumbnail to 0.8 if the width percentage is 80. </param>
/// <Param name = "targetfilepath"> full file name saved by the thumbnail (with Path). Parameter format: D: \ images \ filename.jpg </param>
/// <Returns> success returns true; otherwise, false is returned. </returns>
Public bool getreducedimage (double percent, string targetfilepath)
{
Try
{
Image cecedimage;

Image. getthumbnailimageabort callb = new image. getthumbnailimageabort (thumbnailcallback );

Imagewidth = convert. toint32 (resourceimage. Width * percent );
Imageheight = convert. toint32 (resourceimage. Width * percent );

Performancedimage = resourceimage. getthumbnailimage (imagewidth, imageheight, callb, intptr. Zero );

Performancedimage. Save (@ targetfilepath, imageformat. JPEG );

Cecedimage. Dispose ();

Return true;
}
Catch (exception E)
{
Errmessage = E. message;
Return false;
}
}

}