(Go) Zip Append Files and Entry Type

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Demonstrates appending files to a zip object for writing a .zip. Also explains the "entry type".

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    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    var success bool

    zip := chilkat.NewZip()
    // entry is a ZipEntry

    zipPath := "c:/temp/qa_output/out.zip"

    // Initialize the zip object with the path of the .zip to be created.
    zip.NewZip(zipPath)

    // Recursively append to the zip object the paths of the files and directories in a directory tree.
    // At this point we are not creating the .zip, nor are we reading the contents of the files.
    // We are simply appending references to the files and directories in the local filesystem
    // that will get processed when WriteZip is called.
    recurse := true
    saveExtraPath := false
    archiveOnly := false
    includeHidden := true
    includeSystem := false
    success = zip.AppendFilesEx("c:/temp/files_to_zip",recurse,saveExtraPath,archiveOnly,includeHidden,includeSystem)
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    // Note: We can iterate over the references to the files that will be processed when zipping:
    count := zip.NumEntries()
    i := 0
    for i < count {
        entry := zip.GetEntryByIndex(i)
        fmt.Println(entry.FileName(), " entryType = ", entry.EntryType())
        entry.DisposeZipEntry()
        i = i + 1
    }

    fmt.Println("----")

    // Sample output for the above loop:
    // The entry type = 1, because these are entries that are references to files in the local filesystem
    // that are to be processed when the zip is written.

    // hamlet.xml entryType = 1
    // hello.pdf entryType = 1
    // ...
    // ...

    // Possible entry type values:
    // 0 - Mapped Entry: An entry in an existing Zip file.
    // 1 - File Entry: A file not yet in memory, but referenced. These entries are added by calling AppendFiles, AppendFilesEx, AppendOneFileOrDir, etc.
    // 2 - Data Entry: An entry containing uncompressed data from memory. These entries are added by calling AppendData, AppendString, etc.
    // 3 - Null Entry: An entry that no longer exists in the .zip.
    // 4 - New Directory Entry: A directory entry added by calling AppendNewDir. 

    // The application can continue to add additional entries.
    // For example:
    eTemp := zip.AppendString("helloWorld.txt","Hello World")
    eTemp.DisposeZipEntry()

    // Now let's have a look at what will get zipped when we write the zip:
    count = zip.NumEntries()
    i = 0
    for i < count {
        entry = zip.GetEntryByIndex(i)
        fmt.Println(entry.FileName(), " entryType = ", entry.EntryType())
        entry.DisposeZipEntry()
        i = i + 1
    }

    fmt.Println("----")

    // You can see that "helloWorld.txt" is added. 
    // Its entryType = 2, which means it is in-memory data (it is not a reference to a file in the local filesystem).

    // hamlet.xml entryType = 1
    // hello.pdf entryType = 1
    // ...
    // ...
    // helloWorld.txt entryType = 2

    // ----------------------------------------------------------------------------
    // Now we'll write the zip to a .zip file.
    zip.SetFileName(zipPath)
    success = zip.WriteZip()
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    // Let's look again at the entries in the .zip
    count = zip.NumEntries()
    i = 0
    for i < count {
        entry = zip.GetEntryByIndex(i)
        fmt.Println(entry.FileName(), " entryType = ", entry.EntryType())
        entry.DisposeZipEntry()
        i = i + 1
    }

    fmt.Println("----")

    // After writing the .zip, the entry types change to 0.
    // Entry type 0 indicates that it's a "mapped entry", which is an entry in an existing (and currently open) .zip file.

    // hamlet.xml entryType = 0
    // hello.pdf entryType = 0
    // ...
    // ...
    // helloWorld.txt entryType = 0

    // ----------------------------------------------------------------------------
    // If desired, we could continue adding additional entries of any kind (files or data) to the currently open .zip archive...

    eTemp = zip.AppendString("helloWorld2.txt","Hello World 2")
    eTemp.DisposeZipEntry()

    // Write the .zip, including the new entries..
    success = zip.WriteZip()
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    // Finally, let's look again at the entries in the .zip
    count = zip.NumEntries()
    i = 0
    for i < count {
        entry = zip.GetEntryByIndex(i)
        fmt.Println(entry.FileName(), " entryType = ", entry.EntryType())
        entry.DisposeZipEntry()
        i = i + 1
    }

    fmt.Println("----")

    // hamlet.xml entryType = 0
    // hello.pdf entryType = 0
    // ...
    // ...
    // helloWorld.txt entryType = 0
    // helloWorld2.txt entryType = 0

    zip.CloseZip()

    fmt.Println("Success")

    zip.DisposeZip()