(JavaScript) Remove an Entry from an Existing ZIP Using DeleteEntry

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.

Note: This example requires Chilkat v11.0.0 or greater.

Note

This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.

var success = false;

success = false;

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

var zip = new CkZip();

success = zip.NewZip("original.zip");
if (success == false) {
    console.log(zip.LastErrorText);
    return;
}

var charset = "utf-8";

success = zip.AddString("a.txt","Contents of file A",charset);
if (success == false) {
    console.log(zip.LastErrorText);
    return;
}

success = zip.AddString("b.txt","Contents of file B",charset);
if (success == false) {
    console.log(zip.LastErrorText);
    return;
}

success = zip.AddString("c.txt","Contents of file C",charset);
if (success == false) {
    console.log(zip.LastErrorText);
    return;
}

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

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

var zip2 = new CkZip();

success = zip2.OpenZip("original.zip");
if (success == false) {
    console.log(zip2.LastErrorText);
    return;
}

// Find the entry named "b.txt".
var entry = new CkZipEntry();

success = zip2.EntryOf("b.txt",entry);
if (success == false) {
    console.log(zip2.LastErrorText);
    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) {
    console.log(zip2.LastErrorText);
    return;
}

// Write the modified ZIP archive to a new file.
zip2.FileName = "modified.zip";

success = zip2.WriteZipAndClose();
if (success == false) {
    console.log(zip2.LastErrorText);
    return;
}

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

console.log("ZIP archive updated successfully.");