ASP.NET(vb.net) & Create Thumbnail Image

Author: admin | Posted: 19-06-2010 | Category: ASP.NET(vb.net) & Image

ASP.NET(vb.net) & Create Thumbnail Image - The in this tutorial, you’ll learn and example scripts how to Create image thumbnail using by ASP.NET scripts.

ShotDev Focus:
- ASP.NET(vb.net) & Create Thumbnail Image

Example

AspNetCreateThumbnail.aspx

<%@ Import Namespace="System.Drawing" %>
<%@ Import Namespace="System.Drawing.Imaging" %>
<%@ Import Namespace="System.IO"%>
<%@ Page Language="VB" %>
<script runat="server">

Sub Page_Load(sender As Object, e As EventArgs)
If Not Page.IsPostBack() Then
Me.txtFrom.Text = "Gallery/"
Me.txtTo.Text = "Resize/"
End IF
End Sub

Sub btnCreate_OnClick(sender As Object, e As EventArgs)

Dim myDirInfo As DirectoryInfo
Dim arrFileInfo As Array
Dim myFileInfo As FileInfo
Dim FileName As String
Dim NewFileName As String

Me.lblText.Text = ""

myDirInfo = New DirectoryInfo(Server.MapPath(Me.txtFrom.Text))
arrFileInfo = myDirInfo.GetFiles("*.jpg")
For Each myFileInfo In arrFileInfo
FileName = txtFrom.Text & myFileInfo.Name
NewFileName = txtTo.Text & "Thumbnail_"&myFileInfo.Name

'*** Call to function resize ***'
Call ResizeImages(FileName,NewFileName)

Me.lblText.Text = Me.lblText.Text & (FileName & "===> <a href=" & NewFileName & ">" & NewFileName &"</a><br>")
Next myFileInfo

End Sub

Sub ResizeImages(FileName,NewFileName)
Dim intWidth,intHeight As Integer

intWidth =     100 '*** Fix Width ***'
intHeight = 0   '*** If = 0 Auto Re-Cal Size ***'

Dim objGraphic As System.Drawing.Image = System.Drawing.Image.FromFile(Server.MapPath(FileName))

Dim objBitmap As Bitmap
'*** Calculate Height ***'
If intHeight > 0 Then
objBitmap = New Bitmap(objGraphic, intWidth, intHeight)
Else
If objGraphic.Width > intWidth Then
Dim ratio As Double = objGraphic.Height / objGraphic.Width
intHeight = ratio * intWidth
objBitmap = New Bitmap(objGraphic, intWidth, intHeight)
Else
objBitmap = New Bitmap(objGraphic)
End If
End If

'*** Save As  ***'
objBitmap.Save(Server.MapPath(NewFileName), objGraphic.RawFormat)

'*** Close ***'
objGraphic.Dispose()

'*** Nothing ***'
objBitmap = Nothing
objGraphic = Nothing

End Sub

</script>
<html>
<head>
<title>ShotDev.Com Tutorial</title>
</head>
<body>
<form id="form1" runat="server">
<asp:Label id="lblForm" runat="server" Text="Path From" Width="58px"></asp:Label>
<asp:Textbox id="txtFrom" runat="server"></asp:Textbox><br />
<asp:Label id="lblTo" runat="server" Text="Path To" Width="58px"></asp:Label>
<asp:Textbox id="txtTo" runat="server"></asp:Textbox>
<input id="btnCreate" type="button" OnServerClick="btnCreate_OnClick"  value="Create" runat="server" />
<hr />
<asp:Label id="lblText" runat="server"></asp:Label>
</form>
</body>
</html>

Screenshot