试试：bmp.save("d:\缩略图.jpg",img.RawFormat)
或者试试
Dim file As String = "d:\test.jpg"
Dim bmpSrc As New Bitmap(file)
Dim bmpDest As New Bitmap(500, 500 * (bmpSrc.height / bmpSrc.width),System.Drawing.Imaging.PixelFormat.Format24bppRgb)
Dim g = Graphics.FromImage(bmpDest)
Dim rectDest As New System.Drawing.Rectangle(0, 0, 100, 100)
Dim rectSrc As New System.Drawing.Rectangle(0, 0, bmpSrc.Width, bmpSrc.Height)
g.DrawImage(bmpSrc, rectDest, rectSrc, GraphicsUnit.Pixel)
g.Dispose()
bmpDest.Save("d:\缩略图.jpg",img.RawFormat)
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Post By：2021/4/10 11:16:00 [显示全部帖子]
