CODE EXAMPLE FOR SWIFT

get files with file type swift

let enumerator = FileManager.default.enumerator(atPath: folderPath)
let filePaths = enumerator?.allObjects as! [String]
let txtFilePaths = filePaths.filter{$0.contains(".txt")}
for txtFilePath in txtFilePaths{
    //Here you get each text file path present in folder
    //Perform any operation you want by using its path
}