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If textBox1.Text = "" Then
    MessageBox.Show("You have not typed the URL", "URL Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
Else
    Dim URL As String = textBox1.Text
    'Retriving file extension
    Dim filetype As String = URL.Substring(URL.LastIndexOf(".") + 1, (URL.Length - URL.LastIndexOf(".") - 1))
    filetypevalue.Text = filetype.ToUpper()
    Retriving file name without extension
    Dim filename As String = URL.Substring(URL.LastIndexOf("/") + 1, (URL.Length - URL.LastIndexOf("/") - 1))
    namelabel.Text = filename
    'Requesting for file details
    Dim req As System.Net.WebRequest = System.Net.HttpWebRequest.Create(textBox1.Text)
    req.Method = "HEAD"
    'Retriving the response
    Dim resp As System.Net.WebResponse = req.GetResponse()
    Dim ContentLength As Long = 0
    Dim result As Long
    'Finding the file size
    If Long.TryParse(resp.Headers.Get("Content-Length"), ContentLength) Then
        Dim File_Size As String
        If ContentLength >= 1073741824 Then
            result = ContentLength / 1073741824
            kbmbgb.Text = "GB"
        ElseIf ContentLength >= 1048576 Then
            result = ContentLength / 1048576
            kbmbgb.Text = "MB"
        Else
            result = ContentLength / 1024
            kbmbgb.Text = "KB"
        End If
        File_Size = result.ToString("0.00")
        sizevaluelabel.Text = File_Size
    End If
End If