How to create dynamic thumbnails using ASP. NET

How to create dynamic thumbnails using ASP. NET

This example describes how to create a dynamic thumbnail in ASP. NET. Share it with you for your reference. The specific analysis is as follows:

Tip:

1. import System. IO
2. Create class C lass "CreateThumbnails"
Or any class and place following function inside that class

You need one function to response call back to main function

Function ImageAbortDummyCallback () As Boolean
Return False
End Function

The Code is as follows:

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Function CreateJPEGThumbnail (ByVal inSourceFile As String, ByVal inDestinationFile As String, ByVal ThumbWidth As Integer, ByVal ThumbHeight As Integer) As Boolean Dim imageFile As System. Drawing. Image Dim outputFstream As New FileStream (inSourceFile, FileMode. Open, FileAccess. Read) 'Exposes a System. IO. Stream around a file, supporting both synchronous and asynchronous read and write operations. Dim ImageAbortCallBack As System. Drawing. Image. GetThumbnailImageAbort 'This method returns true if it decides that the System. Drawing. Image. GetThumbnailImage method shocould prematurely stop execution; otherwise, it returns false. ImageFile = System. Drawing. Image. FromStream (outputFstream) ImageAbortCallBack = New System. Drawing. Image. GetThumbnailImageAbort (AddressOf ImageAbortDummyCallback) ImageFile = imageFile. GetThumbnailImage (ThumbWidth, ThumbHeight, ImageAbortCallBack, IntPtr. Zero) 'Intptr = A platform-specific type that is used to represent a pointer or a handle. ImageFile. Save (inDestinationFile, System. Drawing. Imaging. ImageFormat. Jpeg) OutputFstream. Close () OutputFstream = Nothing ImageFile = Nothing End Function

I hope this article will help you design your asp.net program.