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1，Swift继续使用Object-C原有的一套线程，包括三种多线程编程技术：
（1）NSThread
（2）Cocoa NSOperation（NSOperation和NSOperationQueue）
（3）Grand Central Dispath（GCD）
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import UIKitclass ViewController: UIViewController { override func viewDidLoad() { super.viewDidLoad() var operation:NSBlockOperation = NSBlockOperation(block: { [weak self] in self?.downloadImage() return }) //创建一个NSOperationQueue实例并添加operation var queue:NSOperationQueue = NSOperationQueue() queue.addOperation(operation) } //定义一个下载图片的方法，线程调用 func downloadImage(){ var data = NSData(contentsOfURL: NSURL(string: imageUrl)!, options: nil, error: nil) println(data?.length) } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() // Dispose of any resources that can be recreated. }} |
（2）继承NSOperation
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import UIKitclass ViewController: UIViewController { override func viewDidLoad() { super.viewDidLoad() //创建线程对象 var downloadImageOperation:DownloadImageOperation = DownloadImageOperation() //创建一个NSOperationQueue实例并添加operation var queue:NSOperationQueue = NSOperationQueue() queue.addOperation(downloadImageOperation) } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() }}class DownloadImageOperation: NSOperation { override func main(){ var data = NSData(contentsOfURL: NSURL(string: imageUrl)!, options: nil, error: nil) println(data?.length) }} |
4，设置运行队列并发数
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//设置并发数queue.maxConcurrentOperationCount = 5 |
5，取消队列所有操作
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//取消所有线程操作queue.cancelAllOperations() |
6，每个NSOperation完成都会有一个回调表示任务结束
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//定义一个回调var completionBlock:(() -> Void)?//给operation设置回调operation.completionBlock = completionBlockdispatch_after(dispatch_time(DISPATCH_TIME_NOW, 4), dispatch_get_main_queue(), { println("Complete")}) |
Swift - 多线程实现方式（2） - NSOperation和NSOperationQueue
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原文地址：http://www.cnblogs.com/Free-Thinker/p/4841134.html
