(Classic ASP) Set a Custom Last-Modified Date in a Gzip File

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This example demonstrates how to use the SetDt method to specify a custom last-modified date and time that will be embedded in a Gzip file.

A CkDateTime object is first initialized with a specific date/time using an RFC 822 formatted string. This date/time is then applied to the Gzip object using SetDt.

When a compression method is called (such as CompressStringToFile), the specified date/time is included in the Gzip metadata. This allows the resulting .gz file to carry a meaningful timestamp rather than using the current system time.

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<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>
<body>
<%
success = 0

' This example demonstrates how to set a custom last-modified date/time
' that will be embedded in a Gzip file.

set gzip = Server.CreateObject("Chilkat.Gzip")
set dt = Server.CreateObject("Chilkat.CkDateTime")

' Set the date/time using a timestamp format (ISO 8601 style):
success = dt.SetFromTimestamp("2025-11-15T12:45:26-05:00")

' Apply the date/time to the Gzip object:
success = gzip.SetDt(dt)
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( gzip.LastErrorText) & "</pre>"
    Response.End
End If

' Compress a string so the custom date/time is embedded in the .gz:
inputStr = "Example text for Gzip compression."
success = gzip.CompressStringToFile(inputStr,"utf-8","output.gz")
If (success = 0) Then
    Response.Write "<pre>" & Server.HTMLEncode( gzip.LastErrorText) & "</pre>"
    Response.End
End If

Response.Write "<pre>" & Server.HTMLEncode( "Gzip file created with custom last-modified date.") & "</pre>"

%>
</body>
</html>