Swift - 使用URLSession加载数据、下载、上传文件

func sessionLoadData(){
    //创建URL对象
    let urlString = "http://hangge.com"
    let url = URL(string:urlString)
    //创建请求对象
    let request = URLRequest(url: url!)
    
    let session = URLSession.shared
    let dataTask = session.dataTask(with: request,
        completionHandler: {(data, response, error) -> Void in
            if error != nil{
                print(error.debugDescription)
            }else{
                let str = String(data: data!, encoding: String.Encoding.utf8)
                print(str)
            }
    }) as URLSessionTask
    
    //使用resume方法启动任务
    dataTask.resume() 
}

func sessionSimpleDownload(){
    //下载地址
    let url = URL(string: "http://hangge.com/blog/images/logo.png")
    //请求
    let request = URLRequest(url: url!)
    
    let session = URLSession.shared
    //下载任务
    let downloadTask = session.downloadTask(with: request,
           completionHandler: { (location:URL?, response:URLResponse?, error:Error?)
            -> Void in
            //输出下载文件原来的存放目录
            print("location:\(location)")
            //location位置转换
            let locationPath = location!.path
            //拷贝到用户目录
            let documnets:String = NSHomeDirectory() + "/Documents/1.png"
            //创建文件管理器
            let fileManager = FileManager.default
            try! fileManager.moveItem(atPath: locationPath, toPath: documnets)
            print("new location:\(documnets)")
    })
    
    //使用resume方法启动任务
    downloadTask.resume()
}

import UIKit

class ViewController: UIViewController, URLSessionDownloadDelegate {
    
    private lazy var session:URLSession = {
        //只执行一次
        let config = URLSessionConfiguration.default
        let currentSession = URLSession(configuration: config, delegate: self,
                                        delegateQueue: nil)
        return currentSession

    }()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        sessionSeniorDownload()
    }
    
    //下载文件
    func sessionSeniorDownload(){
        //下载地址
        let url = URL(string: "http://hangge.com/blog/images/logo.png")
        //请求
        let request = URLRequest(url: url!)
        
        //下载任务
        let downloadTask = session.downloadTask(with: request)
        
        //使用resume方法启动任务
        downloadTask.resume()
    }

    
    //下载代理方法，下载结束
    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask,
                    didFinishDownloadingTo location: URL) {
        //下载结束
        print("下载结束")
        
        //输出下载文件原来的存放目录
        print("location:\(location)")
        //location位置转换
        let locationPath = location.path
        //拷贝到用户目录
        let documnets:String = NSHomeDirectory() + "/Documents/2.png"
        //创建文件管理器
        let fileManager = FileManager.default
        try! fileManager.moveItem(atPath: locationPath, toPath: documnets)
        print("new location:\(documnets)")
    }
    
    //下载代理方法，监听下载进度
    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask,
                    didWriteData bytesWritten: Int64, totalBytesWritten: Int64,
                    totalBytesExpectedToWrite: Int64) {
        //获取进度
        let written:CGFloat = (CGFloat)(totalBytesWritten)
        let total:CGFloat = (CGFloat)(totalBytesExpectedToWrite)
        let pro:CGFloat = written/total
        print("下载进度：\(pro)")
    }
    
    //下载代理方法，下载偏移
    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask,
                    didResumeAtOffset fileOffset: Int64, expectedTotalBytes: Int64) {
        //下载偏移，主要用于暂停续传
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
}

func sessionUpload(){
    //上传地址
    let url = URL(string: "http://hangge.com/upload.php")
    //请求
    var request = URLRequest(url: url!, cachePolicy: .reloadIgnoringCacheData)
    request.httpMethod = "POST"
    
    let session = URLSession.shared
    
    //上传数据流
    let documents =  NSHomeDirectory() + "/Documents/1.png"
    let imgData = try! Data(contentsOf: URL(fileURLWithPath: documents))
    
    
    let uploadTask = session.uploadTask(with: request, from: imgData) {
        (data:Data?, response:URLResponse?, error:Error?) -> Void in
        //上传完毕后
        if error != nil{
            print(error)
        }else{
            let str = String(data: data!, encoding: String.Encoding.utf8)
            print("上传完毕：\(str)")
        }
    }
    
    //使用resume方法启动任务
    uploadTask.resume()
}

<?php  
/** php 接收流文件 
* @param  String  $file 接收后保存的文件名 
* @return boolean 
*/  
function receiveStreamFile($receiveFile){    
    $streamData = isset($GLOBALS['HTTP_RAW_POST_DATA'])? $GLOBALS['HTTP_RAW_POST_DATA'] : '';  
  
    if(empty($streamData)){  
        $streamData = file_get_contents('php://input');  
    }  
  
    if($streamData!=''){  
        $ret = file_put_contents($receiveFile, $streamData, true);  
    }else{  
        $ret = false;  
    }  
 
    return $ret;    
}  

//定义服务器存储路径和文件名
$receiveFile =  $_SERVER["DOCUMENT_ROOT"]."/uploadFiles/hangge.png";  
$ret = receiveStreamFile($receiveFile);  
echo json_encode(array('success'=>(bool)$ret));  
?>