Public Shared Sub MakeSmallImg(ByVal postFile As System.Web.HttpPostedFile, ByVal saveImg As String, ByVal Width As System.Double, ByVal Height As System.Double)

        Dim originalFilename As String = postFile.FileName         '生成的高质量图片名称         Dim strGoodFile As String = saveImg

        '从文件取得图片对象         Dim image As System.Drawing.Image = System.Drawing.Image.FromStream(postFile.InputStream, True)

        Dim NewWidth, NewHeight As System.Double

        If (image.Width > image.Height) Then

            NewWidth = Width

            NewHeight = image.Height * (NewWidth / image.Width)

        Else

            NewHeight = Height

            NewWidth = (NewHeight / image.Height) * image.Width         End If

        If (NewWidth > Width) Then

            NewWidth = Width

        End If         If (NewHeight > Height) Then

            NewHeight = Height

        End If

        '取得图片大小

        Dim size As System.Drawing.Size = New System.Drawing.Size(CType(NewWidth, Integer), CType(NewHeight, Integer))         '新建一个bmp图片         Dim bitmap As System.Drawing.Image = New System.Drawing.Bitmap(size.Width, size.Height)         '新建一个画板         Dim g As System.Drawing.Graphics = System.Drawing.Graphics.FromImage(bitmap)         '设置高质量插值法         g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High         '设置高质量,低速度呈现平滑程度         g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality         '清空一下画布         g.Clear(Color.White)         '在指定位置画图         g.DrawImage(image, New System.Drawing.Rectangle(0, 0, bitmap.Width, bitmap.Height), New System.Drawing.Rectangle(0, 0, image.Width, image.Height), System.Drawing.GraphicsUnit.Pixel)

        '文字水印

        'System.Drawing.Graphics G=System.Drawing.Graphics.FromImage(bitmap);         'System.Drawing.Font f=new Font("宋体",10);         'System.Drawing.Brush b=new SolidBrush(Color.Black);         'G.DrawString("myohmine",f,b,10,10);         'G.Dispose();

 

        '图片水印

        'System.Drawing.Image copyImage = System.Drawing.Image.FromFile(System.Web.HttpContext.Current.Server.MapPath("pic/1.gif"));         'Graphics a = Graphics.FromImage(bitmap);         'a.DrawImage(copyImage, new Rectangle(bitmap.Width-copyImage.Width,bitmap.Height-copyImage.Height,copyImage.Width, copyImage.Height),0,0, copyImage.Width, copyImage.Height, GraphicsUnit.Pixel);

        'copyImage.Dispose();

        'a.Dispose();         'copyImage.Dispose();

        '保存高清晰度的缩略图         bitmap.Save(strGoodFile, System.Drawing.Imaging.ImageFormat.Jpeg)

        g.Dispose()

        image.Dispose()         bitmap.Dispose()

    End Sub 

MakeSmallImg(PhotoPath.PostedFile, filePath, 140, 185)

本文转自kenty博客园博客，原文链接http://www.cnblogs.com/kentyshang/archive/2006/11/21/566950.html如需转载请自行联系原作者

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