[iOS] UDP Socket 實作-含程式碼 / 完整範例 / Youtube 實測

終於可以把udp socket 做出來了！

每次google 都是那幾篇.....而且每個都寫很不完整(很多都抄同一篇的)

搞了半天什麼CocoaAsyncSocket , GCDAsyncSocket , BSD Socket.....

沒有一篇寫比較完整,後來還好在github上有一個可以用的（不過是for Mac ,not for

iphone) 於是就仿照著寫了以後就可以用了！

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(正文開始）

要寫socket 一定是要分兩部分 server & client , 然後在眾多的library裡面我選擇是：

AsyncUdpSocket

首先,先開一個project,然後add files to (project name)...

把AsyncUdpSocket.h / AsyncUdpSocket.m 加入（放哪邊不重要,不影響）

然後我們需要先到ViewController.h / Main.storyboard來宣告/拉一些物件

這邊（server)會需要一個輸入port 的textfield,一個按鈕 以及一個textview

別忘記要把他們兩邊做連結！


ViewControlloer.h：

//

//  ViewController.h

//  UdpServer

//

//  Created by daniel on 2015/3/13.

//  Copyright (c) 2015年 daniel. All rights reserved.

//

#import <UIKit/UIKit.h>

#import "AsyncUdpSocket.h"

@interface ViewController : UIViewController

{

    AsyncUdpSocket *udpSocket;

}

@property (weak, nonatomic) IBOutlet UITextField *port;

@property (weak, nonatomic) IBOutlet UIButton *start;

@property (weak, nonatomic) IBOutlet UITextView *textview;

- (IBAction)startButton:(id)sender;

@end

接下來就是

ViewController.m:

//

//  ViewController.m

//  UdpServer

//

//  Created by daniel on 2015/3/13.

//  Copyright (c) 2015年 daniel. All rights reserved.

//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

@synthesize port;

@synthesize start;

@synthesize textview;

- (void)viewDidLoad {

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    udpSocket = [[AsyncUdpSocket alloc] initWithDelegate:self];//初始化

    

}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

- (IBAction)startButton:(id)sender {

        //start udp server

        NSLog(@"Socket open");

        int port_int = [port.text intValue];

        if(port_int < 0 || port_int > 65535)

        {

            port_int = 0;

        }

        

        NSError *error = nil;

        

        if (![udpSocket bindToPort:port_int error:&error]) {

            return;

        }

        

        [udpSocket receiveWithTimeout:-1 tag:0];

        [port setEnabled:NO];

}

-(BOOL) onUdpSocket:(AsyncUdpSocket *)sock didReceiveData:(NSData *)data withTag:(long)tag fromHost:(NSString *)host port:(UInt16)port

{

    NSString *msg = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

    if(msg)

    {

        //textview.text  msg;

        NSLog(@"message is %@",msg);

        

        //以下這串是為了讓他能夠顯示在畫面上

        NSString *temp = [NSString stringWithFormat:@"%@\n",msg];

        NSMutableDictionary *attribute = [NSMutableDictionary dictionaryWithCapacity:1];

        NSAttributedString *as = [[NSAttributedString alloc] initWithString:temp attributes:attribute];

        //使用append的方式 ,但是他是NSAttributedString格式 所以才要先轉換,不能直接使用NSString!

        [[textview textStorage] appendAttributedString:as];

    }

    else

    {

        NSLog(@"converting UTF-8 Error");

    }

    [udpSocket sendData:data toHost:host port:port withTimeout:-1 tag:0];

    [udpSocket receiveWithTimeout:-1 tag:0];

    return YES;

}

@end

在viewDidLoad這邊就是app一開始會跑的地方,當然是把socket初始化

然後在button按下去觸發的這個函式(IBAction)startButton:(id)sender )

我們需要把使用者輸入的port 放進int port_int裡面

然後如果使用者輸入數字超過0～65535這個區間 就直接給他port = 0

接著在-(BOOL) onUdpSocket:(AsyncUdpSocket *)sock didReceiveData:(NSData *)data withTag:(long)tag fromHost:(NSString *)host port:(UInt16)port

這一段,我們必須要先宣告一個NSData來接收資料(data),編碼這邊使用UTF-8

如果msg有東西則顯示在螢幕上

記得最後面要加

    [udpSocket sendData:data toHost:host port:port withTimeout:-1 tag:0];

    [udpSocket receiveWithTimeout:-1 tag:0];

不然只能接收一次 !

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然後就是 Client端了

一樣是把兩邊做連結（別忘了要import "AsyncUdpSocket.h")

//

//  ViewController.m

//  UdpClient

//

//  Created by daniel on 2015/3/13.

//  Copyright (c) 2015年 daniel. All rights reserved.

//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

@synthesize addr;

@synthesize port;

@synthesize msg;

@synthesize sendButton;

@synthesize logView;

- (void)viewDidLoad {

    [super viewDidLoad];

    // Do any additional setup after loading the view, typically from a nib.

    

    udpSocket = [[AsyncUdpSocket alloc] initWithDelegate:self];

    NSError *error = nil;

    

    if(![udpSocket bindToPort:0 error:&error])

    {

        NSLog(@"Error binding: %@",error);

        return;

    }

    

    [udpSocket receiveWithTimeout:-1 tag:0];

    

    NSLog(@"Ready");

}

- (void)didReceiveMemoryWarning {

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

-(IBAction)send:(id)sender

{

    NSString *host = [addr text];

    NSLog(@"Address: %@",host);

    

    

    int port_int = [[port text] integerValue];//跟原本的不太一樣

    if(port_int <=0 || port > 65535)

    {

        NSLog(@"Valid port require");

    }

    

    NSString *message = [msg text];

    if (message.length == 0) {

        NSLog(@"Message require");

    }

    

    NSData *data = [message dataUsingEncoding:NSUTF8StringEncoding];

    

    if(data != nil)

        NSLog(@"data = %@",data);

    

    [udpSocket sendData:data toHost:host port:5000 withTimeout:-1 tag:tag];

}

-(void) onUdpSocket:(AsyncUdpSocket *)sock didSendDataWithTag:(long)tag

{

    //you could add checks here

}

- (void)onUdpSocket:(AsyncUdpSocket *)sock didNotSendDataWithTag:(long)tag dueToError:(NSError *)error

{

    // You could add checks here

}

-(BOOL) onUdpSocket:(AsyncUdpSocket *)sock didReceiveData:(NSData *)data withTag:(long)tag fromHost:(NSString *)host port:(UInt16)port

{

    

    NSString *msg = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

    if(msg)

    {

        NSLog(@"Receive: %@",msg);

    }

    else

    {

        NSLog(@"Receive Unknown message from %@:%hu",host,port);

    }

    [udpSocket receiveWithTimeout:-1 tag:0];

    return YES;

}

@end

在viewDidLoad這邊一樣要先初始化udpSocket,然後在sendbutton觸發這個action的

event這邊：

-(IBAction)send:(id)sender

{

    NSString *host = [addr text];

    把使用者輸入的ip放入host變數   

    NSLog(@"Address: %@",host);

    

    

    int port_int = [port text];

    

    把使用者輸入的port放進去port_int變數   

    if(port_int <=0 || port > 65535)

    {

        NSLog(@"Valid port require");

    }

    

    NSString *message = [msg text];

    把使用者輸入的message放進去message變數

    if (message.length == 0) {

        NSLog(@"Message require");

    }

    

    NSData *data = [message dataUsingEncoding:NSUTF8StringEncoding];

    

   把要傳出去的message轉換為NSData型態,編碼使用utf-8

    if(data != nil)

        NSLog(@"data = %@",data);

    

    [udpSocket sendData:data toHost:host port:5000 withTimeout:-1 tag:tag];

    

    這邊為了測試方便直接把port 寫死5000,其實應該要寫port:port_int才對

}

好了！

這樣server / client 都有了 就可以開始通訊拉！

client + server(更新連結@2015.11.17)

https://mega.nz/#!HI0h0ahR!iNpaCRvpT-rwTkJrW-oowWNnUf_GsbD-OxQKmFmNRQg

https://mega.nz/#!yNF2CS6a!QjfL6gMO7qdFJugvKaaVDoUSGgtfU8m_d_XtRM_TVfk 

附上程式碼！

https://www.youtube.com/watch?v=wNX29RxA2K8&feature=youtu.be
https://www.youtube.com/watch?v=mDJv2UHnyZg&feature=youtu.be
附上實測證明可以用