upload and resize multiple files

Question

User-1937266229 posted

 Hey Guys

I have some code that i am using to upload multiple images but i would like the images to be resized on upload.

could anyone be kind enough to give me an example of how this can be implemented ?

I am sorry if this had been asked 10000 times and i have searched for the past 2 days trying to find an answer with no luck :(

Here is my code and i would be very greatfull if anyone can help.

Cheers

Andy

 

<script language="vb" runat="server">
Protected Sub Button1_Click(ByVal sender As Object, _
   ByVal e As System.EventArgs)

   Dim filepath As String = Server.MapPath(".") & "/Images/"
   Dim uploadedFiles As HttpFileCollection = Request.Files
   Dim i As Integer = 0

   Do Until i = uploadedFiles.Count
     Dim userPostedFile As HttpPostedFile = uploadedFiles(i)

     Try
        If (userPostedFile.ContentLength > 0) Then
           Label1.Text += "<u>File #" & (i + 1) & "</u><br>"
           Label1.Text += "File Content Type: " & _
              userPostedFile.ContentType & "<br>"
           Label1.Text += "File Size: " & _
              userPostedFile.ContentLength & "kb<br>"
           Label1.Text += "File Name: " & _
              userPostedFile.FileName & "<br>"

           'random name
           Dim timestamp = year(now) & right("0" & month(now),2) & right("0" & day(now),2) & right("0" & hour(now),2) & right("0" & minute(now),2) & right("0" & second(now),2)

           userPostedFile.SaveAs(filepath & "\" & _
              System.IO.Path.GetFileName(timestamp & "-" & userPostedFile.FileName))

           Label1.Text += "Location where saved: " & _
              filepath & "\" & _
              System.IO.Path.GetFileName(userPostedFile.FileName) & _
              "<p>"
        End If
     Catch ex As Exception
        Label1.Text += "Error:<br>" & ex.Message
     End Try
     i += 1
   Loop
End Sub
</script>

 

 

 

Answer 1

User-1682931557 posted
Hi,

Pls see -- Dynamically resize uploaded images (in C#):
http://www.codeproject.com/KB/web-image/pnguploader.aspx

VB.Net sample is here:
http://www.codeproject.com/KB/graphics/image_croppingVBNet.aspx

Answer 2

User-1937266229 posted

 hey dude

thanks for the links but there were not quite what i was looking for

 i have however managed to piece together some code that does the job perfect.

 

<%@  Import Namespace="System.Drawing" %>
<%@  Import Namespace="System.Drawing.Drawing2D" %>
<%@  Import Namespace="System.Drawing.Imaging" %>
<script language="vb" runat="server">
Protected Sub Button1_Click(ByVal sender As Object, _
   ByVal e As System.EventArgs)

   Dim filepath As String = Server.MapPath(".") & "/Images/"
   Dim uploadedFiles As HttpFileCollection = Request.Files
   Dim i As Integer = 0

   Do Until i = uploadedFiles.Count
     Dim userPostedFile As HttpPostedFile = uploadedFiles(i)

     Try
        If (userPostedFile.ContentLength > 0 ) Then
           'random name
               'Dim timestamp = year(now) & right("0" & month(now),2) & right("0" & day(now),2) & right("0" & hour(now),2) & right("0" & minute(now),2) & right("0" & second(now),2)
           
            Dim RandomString as String = System.Guid.NewGuid().ToString()


                   
            Dim filename As String = userPostedFile.FileName

            ' Create a bitmap of the content of the fileUpload control in memory
            Dim originalBMP As New Bitmap(userPostedFile.InputStream)
           
            ' Calculate the new image dimensions
            Dim origWidth As Integer = originalBMP.Width
            Dim origHeight As Integer = originalBMP.Height
            Dim sngRatio As Integer = origWidth / origHeight
            Dim newWidth As Integer = 300
            Dim newHeight As Integer = newWidth / sngRatio
           
            ' Create a new bitmap which will hold the previous resized bitmap
            Dim newBMP As New Bitmap(originalBMP, newWidth, newHeight)
           
            ' Create a graphic based on the new bitmap
            Dim oGraphics As Graphics = Graphics.FromImage(newBMP)
            ' Set the properties for the new graphic file
            oGraphics.SmoothingMode = SmoothingMode.AntiAlias
            oGraphics.InterpolationMode = InterpolationMode.HighQualityBicubic
           
            ' Draw the new graphic based on the resized bitmap
            oGraphics.DrawImage(originalBMP, 0, 0, newWidth, newHeight)
            ' Save the new graphic file to the server
            newBMP.Save((filepath & RandomString) + filename)
           
            ' Once finished with the bitmap objects, we deallocate them.
            originalBMP.Dispose()
            newBMP.Dispose()
            oGraphics.Dispose()   
           
            Image1.ImageUrl = "All images uploaded"      
            'Label1.Text += filename & "<br/>" & userPostedFile.ContentType
            'Image1.ImageUrl = "Images/" & RandomString & filename
            'Image1.Visible = True

        End If
       
     Catch ex As Exception
        Label1.Text += "Error:<br>" & ex.Message
       
     End Try
     i += 1
   Loop
  
      
      
End Sub
</script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Upload and Resize</title>
</head>
<body>
<form id="form1" runat="server">
<asp:FileUpload ID="fileUpload" runat="server" /><br />
<asp:FileUpload ID="fileUpload2" runat="server" /><br />
<asp:FileUpload ID="fileUpload3" runat="server" /><br />
<asp:FileUpload ID="fileUpload4" runat="server" /><br />
<br /><br />
<asp:Button ID="uploadButton" runat="server" Text="Upload!" OnClick="Button1_Click" />

<br /><br />
<asp:Label ID="label1" runat="server"></asp:Label> <br /><br />

<!--<asp:Image ID="Image1" ImageUrl="" runat="server" Visible="false" /> -->

</form>
</body>
</html>

 that will upload and resize multiple images and add a timestamp at the beginning.

If anyone can improve this code in any way then please feel free too as i am still very new at asp.net.

thanks again for the help.

Andy

Answer 3

User-1937266229 posted

 Hey Dudes

 I am using the above code which seems to work perfect in firefox but fails in IE

I get this error when trying to upload an image

Error:
The given path's format is not supported.

if anyone has any idea how to fix this then i would be most greatfull.

here is my code

<%@  Import Namespace="System.Drawing" %>
<%@  Import Namespace="System.Drawing.Drawing2D" %>
<%@  Import Namespace="System.Drawing.Imaging" %>
<script language="vb" runat="server">
Protected Sub Button1_Click(ByVal sender As Object, _
   ByVal e As System.EventArgs)

   Dim filepath As String = Server.MapPath(".") & "/Images/"
   Dim uploadedFiles As HttpFileCollection = Request.Files
   Dim i As Integer = 0
   Dim uploadedimgs=New ArrayList
  
   Do Until i = uploadedFiles.Count
     Dim userPostedFile As HttpPostedFile = uploadedFiles(i)

     Try
        If (userPostedFile.ContentLength > 0 ) Then
       
           'random name
            Dim RandomString as String = System.Guid.NewGuid().ToString()
                   
            Dim filename As String = userPostedFile.FileName

            ' Create a bitmap of the content of the fileUpload control in memory
            Dim originalBMP As New Bitmap(userPostedFile.InputStream)
           
            ' Calculate the new image dimensions
            Dim origWidth As Integer = originalBMP.Width
            Dim origHeight As Integer = originalBMP.Height
            Dim sngRatio As Integer = origWidth / origHeight
            Dim newWidth As Integer = 300
            Dim newHeight As Integer = newWidth / sngRatio
           
            ' Create a new bitmap which will hold the previous resized bitmap
            Dim newBMP As New Bitmap(originalBMP, newWidth, newHeight)
           
            ' Create a graphic based on the new bitmap
            Dim oGraphics As Graphics = Graphics.FromImage(newBMP)
            ' Set the properties for the new graphic file
            oGraphics.SmoothingMode = SmoothingMode.AntiAlias
            oGraphics.InterpolationMode = InterpolationMode.HighQualityBicubic
           
            ' Draw the new graphic based on the resized bitmap
            oGraphics.DrawImage(originalBMP, 0, 0, newWidth, newHeight)
            ' Save the new graphic file to the server
            newBMP.Save((filepath & RandomString) + filename)

            'add each image to arraylist
            uploadedimgs.Add(RandomString & filename)
            rb.DataSource=uploadedimgs
            rb.DataBind()
           
            ' Once finished with the bitmap objects, we deallocate them.
            originalBMP.Dispose()
            newBMP.Dispose()
            oGraphics.Dispose()   
           
            Label1.Text = "All images uploaded"

        End If
       
     Catch ex As Exception
        Label1.Text += "Error:<br>" & ex.Message
       
     End Try
     i += 1
   Loop
  
End Sub
</script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Upload and Resize</title>
</head>
<body>
<form id="form1" runat="server">
<asp:FileUpload ID="fileUpload" runat="server" /><br />
<asp:FileUpload ID="fileUpload2" runat="server" /><br />
<asp:FileUpload ID="fileUpload3" runat="server" /><br />
<asp:FileUpload ID="fileUpload4" runat="server" /><br />
<br /><br />
<asp:Button ID="uploadButton" runat="server" Text="Upload!" OnClick="Button1_Click" />

<br /><br />
<asp:Label ID="label1" runat="server"></asp:Label> <br /><br />

<asp:DropDownList id="rb" runat="server" />

</form>
</body>
</html>

Cheers

Andy

Answer 4

User-449803809 posted
I am using this code for creating thumbnail (changing image size) Using C#

===============================
public bool ThumbnailCallback()
{
return false;
}

public string resizeImage(string pathFrom, string pathTo, string path)
{
string functionReturnValue = null;

try
{
//Create the delegate
System.Drawing.Image.GetThumbnailImageAbort dummyCallBack = default(System.Drawing.Image.GetThumbnailImageAbort);
dummyCallBack = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);

System.Drawing.Image fullSizeImg = default(System.Drawing.Image);
fullSizeImg = System.Drawing.Image.FromFile(pathFrom);

System.Drawing.Image thumbNailImg = default(System.Drawing.Image);
thumbNailImg = fullSizeImg.GetThumbnailImage(100, 100, dummyCallBack, IntPtr.Zero);

//check and create directories if necessary
if (!Directory.Exists(path))
{
//create it if it doesn't
Directory.CreateDirectory(path);
}

thumbNailImg.Save(pathTo);
//GC.Collect()

//Clean up / Dispose...
thumbNailImg.Dispose();

functionReturnValue = "0";
}

catch (Exception Err)
{
functionReturnValue = Err.Message;
}
return functionReturnValue;
}

============================

converted version to VB
============================
Public Function ThumbnailCallback() As Boolean
Return False
End Function

Public Function resizeImage(ByVal pathFrom As String, ByVal pathTo As String, ByVal path As String) As String

Dim functionReturnValue As String = Nothing
Try
'Create the delegate
Dim dummyCallBack As System.Drawing.Image.GetThumbnailImageAbort = Nothing
dummyCallBack = New System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback)

Dim fullSizeImg As System.Drawing.Image = Nothing
fullSizeImg = System.Drawing.Image.FromFile(pathFrom)

Dim thumbNailImg As System.Drawing.Image = Nothing
thumbNailImg = fullSizeImg.GetThumbnailImage(100, 100, dummyCallBack, IntPtr.Zero)

'check and create directories if necessary
If Not Directory.Exists(path) Then
'create it if it doesn't
Directory.CreateDirectory(path)
End If

thumbNailImg.Save(pathTo)
'GC.Collect()

'Clean up / Dispose...
thumbNailImg.Dispose()

functionReturnValue = "0"

Catch Err As Exception
functionReturnValue = Err.Message
End Try

Return functionReturnValue
End Function
============================

and it's working perfectly with me, you can check www.myphotoup.com , gallery page