【IPHONE开发-OBJECTC入门学习】文件的操作,读写复制文件

转自：http://blog.csdn.net/java886o/article/details/9041547

FileTools.h

FileTools.m

#import "FileTools.h"

@implementation FileTools

//复制文件

+ (void) copyFileWithSrcFile:(NSString*) srcFilePath withBakFile:(NSString*) bakFilePath {

    //1.利用NSFileManager复制文件

    //NSFileManager* manager = [NSFileManager defaultManager];

    //[manager copyItemAtPath:srcFilePath toPath:bakFilePath error:nil];

    //2.利用读原文件,写新文件复制文件

    NSFileManager* fileManager = [NSFileManager defaultManager];

    //创建新文件

    BOOL createResult = [fileManager createFileAtPath:bakFilePath contents:nil attributes:nil];

    if (createResult) {

        NSLog(@"文件创建成功...");

    }else {

        NSLog(@"文件创建失败...");

        return;

    }

    NSFileHandle* inStream = [NSFileHandle fileHandleForReadingAtPath:srcFilePath];

    //特别注意-----必须先创建文件再创建outStream,否则将出现拷贝文件大小为0的问题

    NSFileHandle* outStream = [NSFileHandle fileHandleForWritingAtPath:bakFilePath];

    //初始化变量

    NSInteger readCount = 0;

    NSInteger fileSize = [[self fileLengthWithFile:srcFilePath] intValue];

    NSLog(@"复制的文件大小为:%ld",fileSize);

    BOOL isCanRead = YES;

    NSData* bufferData = nil;

    while(isCanRead) { //如果可以读文件,则开始读文件

        [inStream seekToFileOffset:readCount];

        if ((fileSize - readCount) < (1024 * 8)) { //如果剩下可读的文件小于8K,则直接读取到文件末尾,并保存文件,然后结束读取文件

            bufferData = [inStream readDataToEndOfFile];

            isCanRead = false;

            [outStream writeData:bufferData];

            break;

        }else { //如果剩余的刻度文件大于等于8K,则跳转到已读文件位置,并读取8K的数据,保存文件,然后继续读取

            bufferData = [inStream readDataOfLength:(1024 * 8)];

            readCount+= (1024 * 8);

            [outStream writeData:bufferData];

        }

    }

    [outStream closeFile];

    [inStream closeFile];

    NSLog(@"文件拷贝完成...");

}

//获取文件大小

+ (NSNumber*) fileLengthWithFile:(NSString*) filePath {

    NSFileManager* manager = [NSFileManager defaultManager];

    NSDictionary* attrs = [manager attributesOfItemAtPath:filePath error:nil];

    return [attrs objectForKey:NSFileSize];

}

@end

测试 main.m

#import <Foundation/Foundation.h>
#import "FileTools.h"
int main(int argc, const char * argv[])
{
@autoreleasepool {
NSNumber* size = [FileTools fileLengthWithFile:@"/Users/3g2win/Downloads/ios_development.cer"];
NSLog(@"文件大小:%d",[size intValue]);
[FileTools copyFileWithSrcFile:@"/Users/3g2win/Downloads/ios_development.cer" withBakFile:@"/Users/3g2win/Downloads/ios_development_备份.cer"];
}
return 0;
}

巴特西

【IPHONE开发-OBJECTC入门学习】文件的操作,读写复制文件

最新文章

热门文章