B4X

Set a Custom Last-Modified Date in a Gzip File

See more Gzip Examples

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.

B4X

Dim success As Boolean = False

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

Dim gzip As ChilkatGzip
gzip.Initialize("gzip")
Dim dt As ChilkatDateTime
dt.Initialize

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

'  Apply the date/time to the Gzip object:
success = gzip.SetDt(dt)
If success = False Then
    Log(gzip.LastErrorText)
    Return
End If


'  Compress a string so the custom date/time is embedded in the .gz:
Dim inputStr As String = "Example text for Gzip compression."
success = gzip.CompressStringToFile(inputStr, "utf-8", "output.gz")
If success = False Then
    Log(gzip.LastErrorText)
    Return
End If


Log("Gzip file created with custom last-modified date.")