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一、创建文件 |
说明:自定义文件类,通过NSFileManager 以及NSFileHandle 实现文件的创建和copy,为了控制内存的并发使用,通过控制每次赋值的固定长度来分多次复制:
NSString * path=NSHomeDirectory(); path =[path stringByAppendingPathComponent:@"deskTop/Boby.m"]; NSString * target=NSHomeDirectory(); target =[target stringByAppendingPathComponent:@"deskTop/target.m"]; NSFileManager * manager=[NSFileManager defaultManager]; //校验并且创建文件 if(![manager fileExistsAtPath:path]){ [manager createFileAtPath:path contents:nil attributes:nil]; } if(![manager fileExistsAtPath:target]){ [manager createFileAtPath:target contents:nil attributes:nil]; } NSDictionary * dic=[manager attributesOfItemAtPath:path error:nil]; NSFileHandle * handle=[NSFileHandle fileHandleForReadingAtPath:path]; NSFileHandle * handletTarget=[NSFileHandle fileHandleForWritingAtPath:target]; int total=(int)[dic[@"NSFileSize"] integerValue]; self.totalSize=total; int per=50; int count=total%per==0?total/per:total/per+1; for(int i=0;i<count;i++){ [handle seekToFileOffset:self.nowSize]; NSData *data= [handle readDataOfLength:per]; int tem=per*(i+1); if(tem>total){ tem=total; } self.nowSize=tem; [handletTarget seekToEndOfFile]; [handletTarget writeData:data]; [NSThread sleepForTimeInterval:0.2]; } [handle closeFile]; [handletTarget closeFile];
二、设置观察者 |
说明:自定义使用者,通过设置观察者来动态观察当前文件copy的进度并展示到控制台或者输出到UI,并提供方法接口,启动文件拷贝。
- (id) initWithFile:(FileMake *)files{ self=[super init]; if(self){ self.file= files; [self.file addObserver:self forKeyPath:@"nowSize" options:NSKeyValueObservingOptionNew context:nil]; } return self; } -(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context{ CGFloat all=self.file.totalSize; CGFloat now=[[change objectForKey:@"new"] floatValue]; CGFloat result=now/all; NSLog(@"%.2f",result); //一定不能忘了销毁当前的观察者 if(result==1){ [self.file removeObserver:self forKeyPath:@"nowSize"]; } } - (void) begin{ [self.file startCopy]; }
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原文地址:http://blog.csdn.net/jerehedu/article/details/45195765