(Node.js) File Existence Check

Testing to see if a file exists on the FTP server. The GetSizeByName method is a convenient way to check if a file exists. It will return -1 if the file does not exist, otherwise it returns the size of the file in bytes.

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

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

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

    var ftp = new chilkat.Ftp2();

    ftp.Hostname = "ftp.example.com";
    ftp.Username = "username";
    ftp.Password = "password";

    // Connect and login to the FTP server.
    var success = ftp.Connect();
    if (success !== true) {
        console.log(ftp.LastErrorText);
        return;
    }

    // Set the current remote directory to where the file is located:
    success = ftp.ChangeRemoteDir("something");
    if (success !== true) {
        console.log(ftp.LastErrorText);
        return;
    }

    // Test to see if the file exists by getting the file size by name. 
    // If a -1 is returned, the file does not exist.
    var fileSize = ftp.GetSizeByName("test123.txt");
    if (fileSize < 0) {
        console.log("file does not exist");
    }
    else {
        console.log("file exists and is " + fileSize + " bytes in size");
    }

    success = ftp.Disconnect();

}

chilkatExample();