bash If statement failing

Im working on a bash script to check an ftp site to see if some files exist on it. It works by looping through an array of files using curl to check if the file exists on the ftp server. If it doesnt then curl should output an error which im looking for in my if loop and echoing a result based on it. Code below:

#!/bin/bash

# script variables
ftpaddress=ftpaddress
ftplocation=folderlocation
ftpusername=ftpusername
ftppassword=ftppassword
err="curl: (19) Given file does not exist"

# Initialise array of files
files=( "file1.xml" "file2.xml" "zy.xml" )

for f in "${files[@]}"; do
     result=(curl http://ftp$ftpaddress$ftplocation$f --user $ftpusername:$ftppassword --head)
     if [[ "$result" == "$err" ]]; then 
          echo $f " Does not exist!!!!"
     else
          echo $f "Exists"
     fi 
done

Something about the if loop is failing, ive tried lots of variations on it but have been unable to find one that works. At the moment the result is never matching the error. When I run the curl just from the command line it outputs the error i have set to $err if the file doesnt exist but when running the script the else branch is being selected everytime saying the file does exist. I've even tried setting the error to be*"19"*and it still doesnt match. I've spent a lot of time looking it up and testing it but have had no luck so would appreciate any help that can be given.

Thanks