ASP.NET创建动态缩略图的方法
编程学习 2021-07-04 22:41www.dzhlxh.cn编程入门
这篇文章主要介绍了ASP.NET创建动态缩略图的方法,实例分析了asp.net动态操作图片的相关技巧,需要的朋友可以参考下
本文实例讲述了ASP.NET创建动态缩略图的方法。分享给大家供大家参考。具体分析如下：
提示：
1. 导入 System.IO
2. 创建 类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
具体代码如下：
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 should 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
希望本文所述对大家的asp.net程序设计有所帮助。