IOS7 使用KVO实现大文件copy（复制）
之前的一篇文章里面有说关于大文件的copy，这里介绍一下使用kvo的方式，进行文件copy（复制），其实就是检测文件copy的进度。
代码如下:建立两个类FileHandle和Computer
Computer.m
//
// Computer.m
// FileCopyKVODemo
//
// Created by Durban on 13-12-20.
// Copyright (c) 2013年 WalkerFree. All rights reserved.
//
#import "Computer.h"
#import "FileHandle.h"
@implementation Computer
@synthesize filehandle = _filehandle;
-(id) init
{
self = [super init];
if(self != nil)
{
NSString *homePath = NSHomeDirectory();
NSString *srcPath = [homePath stringByAppendingPathComponent:@"android系统框架的介绍.avi"];
NSString *targetPath = [homePath stringByAppendingPathComponent:@"android系统框架的介绍1.avi"];
_filehandle = [[FileHandle alloc] initWithSrcPath:srcPath withTargetPath:targetPath];
[_filehandle addObserver:self
forKeyPath:@"readSize"
options:NSKeyValueObservingOptionNew
context:nil];
}
return self;
}
-(void) copyAction
{
[_filehandle runCopy];
}
-(void) observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
if([keyPath isEqualToString:@"readSize"])
{
if([object isKindOfClass:[FileHandle class]])
{
NSNumber *readSieNum = [change objectForKey:@"new"];
float readSize = [readSieNum floatValue];
FileHandle *file = (FileHandle *)object;
float fileSize = file.fileSize;
float ret = readSize / fileSize * 100;
NSLog(@"%0.1f%%",ret);
}
}
}
@endComputer.h
// // Computer.h // FileCopyKVODemo // // Created by Durban on 13-12-20. // Copyright (c) 2013年 WalkerFree. All rights reserved. // #import <Foundation/Foundation.h> @class FileHandle; @interface Computer : NSObject @property (nonatomic , strong) FileHandle *filehandle; -(void) copyAction; @end
FileHandle.m
//
// FileHandle.m
// FileCopyKVODemo
//
// Created by Durban on 13-12-20.
// Copyright (c) 2013年 WalkerFree. All rights reserved.
//
#import "FileHandle.h"
@implementation FileHandle
@synthesize srcPath = _srcPath;
@synthesize targetPath = _targetPath;
-(id) initWithSrcPath:(NSString *)srcPath withTargetPath:(NSString *)targetPath;
{
self = [super init];
if(self != nil)
{
_srcPath = [srcPath copy];
_targetPath = [targetPath copy];
}
return self;
}
-(void) runCopy
{
//读取大文件，并写入大文件中
NSFileManager *fileManager = [NSFileManager defaultManager];
// NSString *homePath = NSHomeDirectory();
// NSString *srcPath = [homePath stringByAppendingPathComponent:@"android学习路线图介绍.avi"];
// NSString *targetPath = [homePath stringByAppendingPathComponent:@"android学习路线图介绍1.avi"];
BOOL success = [fileManager createFileAtPath:_targetPath
contents:nil
attributes:nil];
if(success)
{
NSLog(@"成功创建文件 ：%@",_targetPath);
}
NSFileHandle *infile = [NSFileHandle fileHandleForWritingAtPath:_targetPath];
NSFileHandle *outfile = [NSFileHandle fileHandleForReadingAtPath:_srcPath];
//获取文件的尺寸
NSDictionary *fileAttr = [fileManager attributesOfItemAtPath:_srcPath
error:nil];
NSNumber *fileSizeNum = [fileAttr objectForKey:NSFileSize];
BOOL isEnd = NO;
self.fileSize = [fileSizeNum longLongValue];
while (!isEnd) {
NSData *data = nil;
NSInteger subleng = self.fileSize - _readSize;
if(subleng < 500)
{
isEnd = YES;
data = [outfile readDataToEndOfFile];
}
else
{
data = [outfile readDataOfLength:500];
self.readSize += 500;
[outfile seekToFileOffset:_readSize];
}
[infile writeData:data];
}
[infile closeFile];
[outfile closeFile];
}
@endFileHandle.h
// // FileHandle.h // FileCopyKVODemo // // Created by Durban on 13-12-20. // Copyright (c) 2013年 WalkerFree. All rights reserved. // #import <Foundation/Foundation.h> @interface FileHandle : NSObject @property (nonatomic, strong) NSString *srcPath; @property (nonatomic, strong) NSString *targetPath; @property (nonatomic ,assign) float fileSize; @property (nonatomic, assign) float readSize; -(id) initWithSrcPath:(NSString *)srcPath withTargetPath:(NSString *)targetPath; -(void) runCopy; @end
示例调用的代码-实现过程是这样子的：
//
// main.m
// FileCopyKVODemo
//
// Created by Durban on 13-12-20.
// Copyright (c) 2013年 WalkerFree. All rights reserved.
//
#import <Foundation/Foundation.h>
#import "Computer.h"
int main(int argc, const char * argv[])
{
@autoreleasepool {
Computer *computer = [[Computer alloc] init];
[computer copyAction];
// insert code here...
NSLog(@"Hello, World!");
}
return 0;
}gowhich得到的结果是，文件进行了完整的copy，并且能进行正常使用，没有出现文件损坏。看看结果吧。
2013-12-20 10:13:43.356 FileCopyKVODemo[8446:303] 成功创建文件 ：/Users/davidzhang/android系统框架的介绍1.avi 2013-12-20 10:13:43.789 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.883 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.884 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.884 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.885 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.885 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.886 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.886 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:43.887 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.139 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.140 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.141 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.141 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.142 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.142 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.143 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.143 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.144 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.145 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:44.145 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.041 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.041 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.042 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.043 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.043 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.054 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.055 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.056 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.056 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.057 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.057 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.058 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.058 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.633 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.634 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.635 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.635 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.636 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.636 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.637 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.637 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.638 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.639 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.639 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.640 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.640 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.640 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.641 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.641 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.642 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.642 FileCopyKVODemo[8446:303] 0.0% 2013-12-20 10:13:46.643 FileCopyKVODemo[8446:303] 0.0% 。。。。。。
这里自己可以进行调整的，比如百分比的小数位可以调整大点，都是可以的。
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由 durban创作并维护的 Gowhich博客采用创作共用保留署名-非商业-禁止演绎4.0国际许可证。
本文首发于
博客（
https://www.gowhich.com ），版权所有，侵权必究。
本文永久链接： https://www.gowhich.com/blog/517
版权声明
由 durban创作并维护的 Gowhich博客采用创作共用保留署名-非商业-禁止演绎4.0国际许可证。
本文首发于 Gowhich博客（ https://www.gowhich.com ），版权所有，侵权必究。
本文永久链接： https://www.gowhich.com/blog/517