socket数据传输，并不复杂

下面是我之前写的FTP上传图片的类

#import <Foundation/Foundation.h>

#include <CFNetwork/CFNetwork.h>

enum {

    kSendBufferSize = 32768

};

@protocol updateHeadImage <NSObject>

- (void)updateHeadImageSuccess:(BOOL )success;

@end

@interface FTPEngine : NSObject <NSStreamDelegate>

{

    uint8_t _buffer[kSendBufferSize];

}

@property (nonatomic, retain)NSArray *pathArr;

@property (nonatomic, assign)NSInteger p;

+ (FTPEngine *)sharedEngine;

- (void)sendImagefilePath:(NSString *)imageFilePath :(NSInteger)i;

@property (nonatomic,weak) id<updateHeadImage>delegate;

@end

#import "FTPEngine.h"

@interface FTPEngine ()

//内部变量

@property (nonatomic, readonly) BOOL              isSending;

@property (nonatomic, retain)   NSOutputStream *  networkStream;

@property (nonatomic, retain)   NSInputStream *   fileStream;

@property (nonatomic, readonly) uint8_t *         buffer;

@property (nonatomic, assign)   size_t            bufferOffset;

@property (nonatomic, assign)   size_t            bufferLimit;

@property (nonatomic ,assign)NSInteger q;

@end

@implementation FTPEngine

+ (FTPEngine *)sharedEngine

{

    static FTPEngine *engine = nil;

    static dispatch_once_t once;

    dispatch_once(&once, ^{

        engine = [[FTPEngine alloc] init];

    });

    return engine;

}

- (uint8_t *)buffer

{

    return self->_buffer;

}

- (void)sendImagefilePath:(NSString *)imageFilePath :(NSInteger)i

{

    self.q = i;

    NSURL *url;//ftp服务器地址

    NSString *filePaths;//图片地址

    NSString *account;//账号

    NSString *password;//密码

    CFWriteStreamRef ftpStream;

    

    filePaths = imageFilePath;

    account = @"ftp";

    password = @"123456";

    if (i == 0)

    {

        url = [NSURL URLWithString:@"ftp://192.168.1.188:21/emot"];

    }

    else if (i == 1)

    {

        url = [NSURL URLWithString:@"ftp://192.168.1.188:21/product"];

    }

    else if (i == 2)

    {

        url = [NSURL URLWithString:@"ftp://192.168.1.188:21/idcard"];

    }

    //添加后缀（文件名称）

    url = (__bridge NSURL *)(CFURLCreateCopyAppendingPathComponent(NULL, (CFURLRef) url, (CFStringRef) [filePaths lastPathComponent], false));

    

    //读取文件，转化为输入流

    self.fileStream = [NSInputStream inputStreamWithFileAtPath:filePaths];

    [self.fileStream open];

    

    //为url开启CFFTPStream输出流

    

    ftpStream = CFWriteStreamCreateWithFTPURL(NULL, (__bridge CFURLRef) url);

    self.networkStream = (__bridge NSOutputStream *) ftpStream;

    

    //设置ftp账号密码

    [self.networkStream setProperty:account forKey:(id)kCFStreamPropertyFTPUserName];

    [self.networkStream setProperty:password forKey:(id)kCFStreamPropertyFTPPassword];

    

    //设置networkStream流的代理，任何关于networkStream的事件发生都会调用代理方法

    self.networkStream.delegate = self;

    

    //设置runloop

    [self.networkStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];

    [self.networkStream open];

    

    //完成释放链接

    CFRelease(ftpStream);

}

#pragma mark 回调方法

- (void)stream:(NSStream *)aStream handleEvent:(NSStreamEvent)eventCode

{

    //aStream 即为设置为代理的networkStream

    switch (eventCode) {

        case NSStreamEventOpenCompleted: {

        } break;

        case NSStreamEventHasBytesAvailable: {

            assert(NO);     // 在上传的时候不会调用

        } break;

        case NSStreamEventHasSpaceAvailable: {

            if (self.bufferOffset == self.bufferLimit) {

                NSInteger   bytesRead;

                bytesRead = [self.fileStream read:self.buffer maxLength:kSendBufferSize];

                

                if (bytesRead == -1) {

                    //读取文件错误

                    [self _stopSendWithStatus:@"读取文件错误"];

                } else if (bytesRead == 0) {

                    //文件读取完成 上传完成

                    [self _stopSendWithStatus:nil];

                } else {

                    self.bufferOffset = 0;

                    self.bufferLimit  = bytesRead;

                }

            }

            

            if (self.bufferOffset != self.bufferLimit)

            {

                //写入数据

                NSInteger bytesWritten;//bytesWritten为成功写入的数据

                bytesWritten = [self.networkStream write:&self.buffer[self.bufferOffset] maxLength:self.bufferLimit - self.bufferOffset];

                assert(bytesWritten != 0);

                if (bytesWritten == -1) {

                    [self _stopSendWithStatus:@"网络写入错误"];

                } else {

                    self.bufferOffset += bytesWritten;

                }

            }

        } break;

        case NSStreamEventErrorOccurred: {

            [self _stopSendWithStatus:@"Stream打开错误"];

            assert(NO);

        } break;

        case NSStreamEventEndEncountered: {

            // 忽略

        } break;

        default: {

            assert(NO);

        } break;

    }

}

//结果处理

- (void)_stopSendWithStatus:(NSString *)statusString

{

    if (self.networkStream != nil) {

        [self.networkStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];

        self.networkStream.delegate = nil;

        [self.networkStream close];

        self.networkStream = nil;

    }

    if (self.fileStream != nil) {

        [self.fileStream close];

        self.fileStream = nil;

    }

    [self _sendDidStopWithStatus:statusString];

}

- (void)_sendDidStopWithStatus:(NSString *)statusString

{

    if (statusString == nil)

    {

        NSLog(@"上传成功！！！");

        if (self.p < self.pathArr.count)

        {

            [self sendImagefilePath:self.pathArr[self.p] :self.q];

            self.p = self.p + 1;

        }

        else

        {

            if ([self.delegate respondsToSelector:@selector(updateHeadImageSuccess:)]) {

                [self.delegate updateHeadImageSuccess:YES];

                return;

                

            }

        }

        

    }

    if ([self.delegate respondsToSelector:@selector(updateHeadImageSuccess:)]) {

        [self.delegate updateHeadImageSuccess:NO];

    }

}

@end