(Node.js) Iterate Over ZIP Entries Using EntryAt

This example demonstrates how to use the EntryAt method to iterate over all entries contained within a ZIP archive.

The EntryAt method retrieves a ZipEntry object for a given zero-based index.

This is useful for:

• Enumerating all entries in a ZIP archive
• Inspecting filenames, sizes, and timestamps
• Searching or filtering ZIP contents

Suppose the ZIP archive contains:

docs/readme.txt
images/logo.png
data/config.json

The example loops through all ZIP entries and prints information about each entry.

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

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOS

var os = require('os');
if (os.platform() == 'win32') {  
  var chilkat = require('@chilkat/ck-node23-win64'); 
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node23-linux-arm');
    } else if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node23-linux-arm64');
    } else {
        var chilkat = require('@chilkat/ck-node23-linux-x64');
    }
} else if (os.platform() == 'darwin') {
  var chilkat = require('@chilkat/ck-node23-mac-universal');
}

function chilkatExample() {

    var success = false;

    success = false;

    // Open an existing ZIP archive.
    var zip = new chilkat.Zip();

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

    // Get the total number of entries in the ZIP archive.
    var numEntries = zip.NumEntries;

    console.log("Number of ZIP entries = " + numEntries);

    // Create a ZipEntry object that will be reused
    // for each entry retrieved by EntryAt.
    var entry = new chilkat.ZipEntry();

    // Iterate over all ZIP entries.
    var i = 0;
    while (i < numEntries) {

        // Retrieve the entry at index i.
        success = zip.EntryAt(i,entry);
        if (success == false) {
            console.log(zip.LastErrorText);
            return;
        }

        console.log("Entry " + i);
        console.log("  FileName: " + entry.FileName);
        console.log("  Uncompressed Length: " + entry.UncompressedLength);
        console.log("  Compressed Length: " + entry.CompressedLength);
        console.log("");

        i = i+1;
    }

    // Sample output:
    // 
    // Entry 0
    //   FileName: docs/readme.txt
    //   Uncompressed Length: 1204
    //   Compressed Length: 512
    // 
    // Entry 1
    //   FileName: images/logo.png
    //   Uncompressed Length: 84211
    //   Compressed Length: 84102
    // 

    zip.CloseZip();

    console.log("Done.");

}

chilkatExample();