I want to learn zip file from the link below but got an error said that "ZipArchive is not defined"
How to fix it?
(I used vs2015, win7, framework 4.5)


Imports System.IO
Imports System.IO.Compression

Module Module1

Sub Main()
Dim zipPath As String = "c:\example\start.zip"
Dim extractPath As String = "c:\example\extract"

Using archive As ZipArchive = ZipFile.OpenRead(zipPath)
For Each entry As ZipArchiveEntry In archive.Entries
If entry.FullName.EndsWith(".txt", StringComparison.OrdinalIgnoreCase) Then
entry.ExtractToFile(Path.Combine(extractPath, entry.FullName))
End If
End Using
End Sub

End Module