Delete files from directory inside Document directory?

Swift 4.0 example that removes all files from an example folder "diskcache" in the documents directory. I found the above examples unclear because they used the NSTemporaryDirectory() + filePath which is not "url" style. For your convenience:

    func clearDiskCache() {
        let fileManager = FileManager.default
        let myDocuments = fileManager.urls(for: .documentDirectory, in: .userDomainMask).first!
        let diskCacheStorageBaseUrl = myDocuments.appendingPathComponent("diskCache")
        guard let filePaths = try? fileManager.contentsOfDirectory(at: diskCacheStorageBaseUrl, includingPropertiesForKeys: nil, options: []) else { return }
        for filePath in filePaths {
            try? fileManager.removeItem(at: filePath)
        }
    }

In case anyone needs this for the latest Swift / Xcode versions: here is an example to remove all files from the temp folder:

Swift 2.x:

func clearTempFolder() {
    let fileManager = NSFileManager.defaultManager()
    let tempFolderPath = NSTemporaryDirectory()
    do {
        let filePaths = try fileManager.contentsOfDirectoryAtPath(tempFolderPath)
        for filePath in filePaths {
            try fileManager.removeItemAtPath(tempFolderPath + filePath)
        }
    } catch {
        print("Could not clear temp folder: \(error)")
    }
}

Swift 3.x and Swift 4:

func clearTempFolder() {
    let fileManager = FileManager.default
    let tempFolderPath = NSTemporaryDirectory()
    do {
        let filePaths = try fileManager.contentsOfDirectory(atPath: tempFolderPath)
        for filePath in filePaths {
            try fileManager.removeItem(atPath: tempFolderPath + filePath)
        }
    } catch {
        print("Could not clear temp folder: \(error)")
    }
}

Swift 3:

 func clearTempFolder() {
    let fileManager = FileManager.default
    let tempFolderPath = NSTemporaryDirectory()

    do {
        let filePaths = try fileManager.contentsOfDirectory(atPath: tempFolderPath)
        for filePath in filePaths {
            try fileManager.removeItem(atPath: NSTemporaryDirectory() + filePath)
        }
    } catch let error as NSError {
        print("Could not clear temp folder: \(error.debugDescription)")
    }
}

Two things, use the temp directory and second pass an error to the fileManager.removeItemAtPath and place it in a if to see what failed. Also you should not be checking if the error is set but rather whether a methods has return data.

func clearAllFilesFromTempDirectory(){

    var error: NSErrorPointer = nil
    let dirPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] as! String
    var tempDirPath = dirPath.stringByAppendingPathComponent("Temp")
    var directoryContents: NSArray = fileManager.contentsOfDirectoryAtPath(tempDirPath, error: error)?

    if directoryContents != nil {
        for path in directoryContents {
            let fullPath = dirPath.stringByAppendingPathComponent(path as! String)
            if fileManager.removeItemAtPath(fullPath, error: error) == false {
                println("Could not delete file: \(error)")
            }
        }
    } else {
        println("Could not retrieve directory: \(error)")
    }
}

To get the correct temporary directory use NSTemporaryDirectory()