VB.NET

Unzip a Text File Entry into a StringBuilder Using ZipEntry.UnzipToSb

See more Zip Examples

This example demonstrates how to use the ZipEntry.UnzipToSb method to inflate a text file entry directly into a StringBuilder object.

The ZIP entry is uncompressed entirely in memory and appended to the StringBuilder without creating a temporary file on disk.

This is useful when:

• Processing text files directly in memory
• Avoiding temporary filesystem files
• Reading configuration files, JSON, XML, CSV, or source code from ZIP archives
• Automatically converting line endings while inflating the text

The srcCharset argument specifies how the uncompressed bytes should be interpreted, such as:

• utf-8
• utf-16
• windows-1252

The lineEndingBehavior argument controls line-ending conversion:

• 0 — Leave line endings unchanged
• 1 — Convert all line endings to bare LF
• 2 — Convert all line endings to CRLF

Suppose the ZIP archive contains:

config/settings.json

The example inflates the JSON file directly into a StringBuilder.

VB.NET

Dim success As Boolean = False

Dim zip As New Chilkat.Zip

' Open an existing ZIP archive.
success = zip.OpenZip("qa_data/zips/configFiles.zip")
If (success = False) Then
    Debug.WriteLine(zip.LastErrorText)
    Exit Sub
End If


' Locate the JSON file entry within the ZIP archive.
Dim entry As New Chilkat.ZipEntry

success = zip.EntryOf("config/settings.json",entry)
If (success = False) Then
    Debug.WriteLine("ZIP entry not found.")
    zip.CloseZip()
    Exit Sub
End If


' ------------------------------------------------------------
' Inflate the ZIP entry directly into a StringBuilder.
' 
' The uncompressed text is appended to the StringBuilder.
' 
Dim sb As New Chilkat.StringBuilder

' Leave line endings unchanged.
Dim lineEndingBehavior As Integer = 0

' Interpret the uncompressed bytes as UTF-8 text.
Dim srcCharset As String = "utf-8"

success = entry.UnzipToSb(lineEndingBehavior,srcCharset,sb)
If (success = False) Then
    Debug.WriteLine(entry.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("Uncompressed text:")
Debug.WriteLine("")
Debug.WriteLine(sb.GetAsString())

zip.CloseZip()

Debug.WriteLine("Done.")