(JavaScript) 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.

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;

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

var ftp = new CkFtp2();

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

// Connect and login to the FTP server.
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();