sto' utilizzando uno script aspx che ridimensiona sul server le immagini prima di caricarle sul client, al fine di ottimizzare i tempi di caricamento della pagina
Il problema che mi si pone e' che funziona SOLO SE
Altezza < Larghezza
anche di un solo pixel
come mai ?
guarda questa pagina
http://www.erlupacchiotto.com/prova/Foto/FotoRedim.html
solo la foto di dx viene caricata, quella al centro invece no
grazie a tutti anticipatamente
-------redim.html----------
PROVA FOTO 90*90
[img]resize.aspx?src=Foto4.jpg&w=150&h=150[/img]
PROVA FOTO 90*89
[img]resize.aspx?src=Foto5.jpg&w=150&h=150[/img]
-------resize.aspx----------
<%@ import namespace="System" %>
<%@ import namespace="System.Drawing" %>
<%@ import namespace="System.Drawing.Imaging" %>
<%@ import namespace="System.IO" %>
<script runat="server">
Function NewthumbSize(currentwidth, currentheight)
' Calculate the Size of the New image
dim k,a,b,c,d as Double
k=currentwidth/currentheight
a=currentwidth
b=currentheight
c=Request.QueryString("h")
d=Request.QueryString("w")
'if (k<=1 and currentheight>=c) then
'a=c*k
'b=c
'end if
if (k>1) then
a=d
b=d/k
else
a=c*k
b=c
end if
dim NewSize as New Size(a, b)
return NewSize
End Function
Sub sendFile()
' create New image and bitmap objects. Load the image file and put into a resized bitmap.
dim g as System.Drawing.Image = System.Drawing.Image.FromFile(server.mappath(reque st("src")))
'dim g as System.Drawing.Image = System.Drawing.Image.FromFile(request("src"))
' initialise the web object
'Dim webC As New System.Net.WebClient()
' set the URL
'Dim strFilename as string
'if Request.QueryString("src")="" then
' strFilename="http://127.0.0.1/chiave.jpg"
'else
' strFilename="http://127.0.0.1/thumbaspx/"&Request.QueryString("src")
'end if
' create a bitmap based on the image from the URL
'Dim g = New System.Drawing.Bitmap(webC.OpenRead(strFilename))
dim thisFormat=g.rawformat
dim thumbSize as New size
thumbSize=NewthumbSize(g.width,g.height)
dim imgOutput as New Bitmap(g, thumbSize.width, thumbSize.height)
' Set the contenttype
'if thisformat.equals(system.drawing.imaging.imageform at.Gif) then
'response.contenttype="image/gif"
'else
response.contenttype="image/jpeg"
'end if
' send the resized image to the viewer
imgOutput.save(response.outputstream, thisformat) ' output to the user
' tidy up
g.dispose()
imgOutput.dispose()
end sub
Sub sendError()
' if no height, width, src then output "error"
dim imgOutput as New bitmap(120, 120, pixelformat.format24bpprgb)
dim g as graphics = graphics.fromimage(imgOutput)
'create a New graphic object from the above bmp
g.clear(color.yellow) ' blank the image
g.drawString("ERRORE!", New font("verdana",14,fontstyle.bold),systembrushes.wi ndowtext,new pointF(2,2))
' Set the contenttype
response.contenttype="image/jpeg"
' send the resized image to the viewer
imgOutput.save(response.outputstream, imageformat.jpeg) ' output to the user
' tidy up
g.dispose()
imgOutput.dispose()
end sub
</script>
<%
' make sure Nothing has gone to the client
response.clear
if request("src")="" then
call sendError()
else
if file.exists(server.mappath(request("src"))) then
call sendFile()
else
call sendError()
end if
end if
response.end
%>
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