Go Requires Chilkat v11.0.0+

Remove an Entry from an Existing ZIP Using DeleteEntry

See more Zip Examples

This example demonstrates how to use the DeleteEntry method to remove a file from an existing ZIP archive.

The example:

• Creates a ZIP archive containing three text files
• Opens the ZIP archive for modification
• Finds and deletes one entry
• Writes the modified ZIP archive to a new filename

Suppose the original ZIP archive contains:

a.txt
b.txt
c.txt

After deleting b.txt, the modified ZIP archive contains:

a.txt
c.txt

The entry is removed only from the in-memory ZIP object until a Write* method is called.

Go

    success := false

    //  ------------------------------------------------------------
    //  First create a ZIP archive containing three text files.

    zip := chilkat.NewZip()

    success = zip.NewZip("original.zip")
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    charset := "utf-8"

    success = zip.AddString("a.txt","Contents of file A",charset)
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    success = zip.AddString("b.txt","Contents of file B",charset)
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    success = zip.AddString("c.txt","Contents of file C",charset)
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    //  Write the ZIP archive to disk.
    //  
    //  The ZIP now contains:
    //  
    //      a.txt
    //      b.txt
    //      c.txt
    //  
    success = zip.WriteZipAndClose()
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    //  ------------------------------------------------------------
    //  Open the existing ZIP archive for modification.

    zip2 := chilkat.NewZip()

    success = zip2.OpenZip("original.zip")
    if success == false {
        fmt.Println(zip2.LastErrorText())
        zip.DisposeZip()
        zip2.DisposeZip()
        return
    }

    //  Find the entry named "b.txt".
    entry := chilkat.NewZipEntry()

    success = zip2.EntryOf("b.txt",entry)
    if success == false {
        fmt.Println(zip2.LastErrorText())
        zip.DisposeZip()
        zip2.DisposeZip()
        entry.DisposeZipEntry()
        return
    }

    //  Remove the entry from the in-memory ZIP object.
    //  
    //  At this point, the original ZIP file on disk is unchanged.
    //  The deletion takes effect only after WriteZip or
    //  WriteZipAndClose is called.
    success = zip2.DeleteEntry(entry)
    if success == false {
        fmt.Println(zip2.LastErrorText())
        zip.DisposeZip()
        zip2.DisposeZip()
        entry.DisposeZipEntry()
        return
    }

    //  Write the modified ZIP archive to a new file.
    zip2.SetFileName("modified.zip")

    success = zip2.WriteZipAndClose()
    if success == false {
        fmt.Println(zip2.LastErrorText())
        zip.DisposeZip()
        zip2.DisposeZip()
        entry.DisposeZipEntry()
        return
    }

    //  The modified ZIP now contains:
    //  
    //      a.txt
    //      c.txt
    //  

    fmt.Println("ZIP archive updated successfully.")

    zip.DisposeZip()
    zip2.DisposeZip()
    entry.DisposeZipEntry()