OC socket简单使用案例

//
//  ViewController.m
//  socket
//
//  Created by admin on 2018/1/18.
//  Copyright © 2018年 admin. All rights reserved.
//

#import "ViewController.h"

#import <sys/socket.h>
#import <netinet/in.h>
#import <arpa/inet.h>

@interface ViewController ()

@property (weak, nonatomic) IBOutlet UITextField *ipTextField;
@property (weak, nonatomic) IBOutlet UITextField *portField;

@property (weak, nonatomic) IBOutlet UIButton *connectBtn;
@property (weak, nonatomic) IBOutlet UIButton *closeBtn;
@property (weak, nonatomic) IBOutlet UIButton *sendBtn;
@property (weak, nonatomic) IBOutlet UITextField *sendMsgField;
@property (weak, nonatomic) IBOutlet UILabel *recvLabel;




@property (nonatomic, assign) int clientSocket;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
}
//点击连接按钮
- (IBAction)connectBtnAction:(id)sender {
    [self connect:self.ipTextField.text port:[self.portField.text intValue]];
}
//点击发送按钮

- (IBAction)sendBtnAction:(id)sender {
    self.recvLabel.text = [self sendAndRecv:self.sendMsgField.text];
    NSLog(@"完毕");
}
//点击关闭按钮

- (IBAction)closeBtnAction:(id)sender {
    close(self.clientSocket);
    NSLog(@"连接关闭");
}

//1.连接服务器
- (BOOL)connect:(NSString *)ip port:(int)port{
    //创建socket
    int clientSocket= socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    
    self.clientSocket = clientSocket;
    
    struct sockaddr_in addr;
    addr.sin_family = AF_INET;
    addr.sin_addr.s_addr = inet_addr(ip.UTF8String);
    addr.sin_port = htons(port);
    int result = connect(clientSocket, (const struct sockaddr *) &addr, sizeof(addr));
    if (result == 0) {
        return YES;
    }else{
        return NO;
    }
}

//1.发送和接受数据
- (NSString *)sendAndRecv:(NSString *)sendMsg{
    //向服务器发送数据
    const char *msg = sendMsg.UTF8String;
    //成功发送返回发送的字节数, 失败返回-1
    ssize_t sendCount = send(self.clientSocket, msg, strlen(msg), 0);
    NSLog(@"发送的字节数%zd", sendCount);
    
    //接受服务器返回的数据
    //返回的是实际接受的字节个数
    uint8_t buffer[1024];
    ssize_t recvCount = recv(self.clientSocket, buffer, sizeof(buffer), 0);
    NSLog(@"接收的字节数%zd", recvCount);
    
    NSData *data = [NSData dataWithBytes:buffer length:recvCount];
    NSString *recvMsg = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
    
    return recvMsg;
}











@end