iOS 实现文件的拷贝详解手机开发

 #import <Foundation/Foundation.h> 
 
//实现文件的拷贝 
 
#define SRCPATH @"/Users/guoyule/Desktop/emailreceipt_20150214R3887454299_new.pdf" 
 
#define DSTPATH @"/Users/guoyule/Desktop/emailreceipt_20150214R3887454299_new1.pdf" 
 
#define PERROR (error) if(error){NSLog(@"%@",error);exit(-1);} 
 
#define BUFF 100 
 
//缓冲区大小 
 
int main(int argc, const char * argv[]) { 
 
    @autoreleasepool { 
 
 
        //所谓文件拷贝 就是从原文件里读往目的文件里写 
 
        //首先创建文件 
 
        NSFileManager * fm =[NSFileManager defaultManager]; 
 
        NSError * error = nil; 
 
        //获取源文件的属性 
 
        NSDictionary *attributes = [fm attributesOfItemAtPath:SRCPATH error:&error]; 
 
//        PERROR(error); 
 
        if(error){NSLog(@"%@",error);exit(-1);}; 
 
        //创建新文件 
 
       BOOL ret = [fm createFileAtPath:DSTPATH contents:nil attributes:attributes]; 
 
        if (!ret) { 
 
            perror("createFile"); 
 
            exit(-1); 
 
        } 
 
        //打开文件句柄 
 
           NSFileHandle * srcFh = [NSFileHandle fileHandleForReadingAtPath:SRCPATH]; 
 
        NSFileHandle * dstFh = [NSFileHandle fileHandleForWritingAtPath:DSTPATH]; 
 
        //不要一口气就将源文件读入内存 
 
        //首先要获取源文件大小 
 
//        size_t size = [[attributes objectForKey:@"NSFileSize"] integerValue]; 
 
        unsigned long long size = [attributes fileSize]; 
 
        //这是一个方法，只有当字典中装文件属性才有效 实际上是一个类别 
 
        /* 
 
         @interface NSDictionary (NSFileAttributes) 
 
          
 
         - (unsigned long long)fileSize; 
 
         - (NSDate *)fileModificationDate; 
 
         - (NSString *)fileType; 
 
         - (NSUInteger)filePosixPermissions; 
 
         - (NSString *)fileOwnerAccountName; 
 
         - (NSString *)fileGroupOwnerAccountName; 
 
         - (NSInteger)fileSystemNumber; 
 
         - (NSUInteger)fileSystemFileNumber; 
 
         - (BOOL)fileExtensionHidden; 
 
         - (OSType)fileHFSCreatorCode; 
 
         - (OSType)fileHFSTypeCode; 
 
         - (BOOL)fileIsImmutable; 
 
         - (BOOL)fileIsAppendOnly; 
 
         - (NSDate *)fileCreationDate; 
 
         - (NSNumber *)fileOwnerAccountID; 
 
         - (NSNumber *)fileGroupOwnerAccountID; 
 
         @end 
 
 
         */ 
 
        while (size) { 
 
            NSData * data =  nil; 
 
            if (size <= BUFF) { 
 
                data = [srcFh readDataToEndOfFile]; 
 
                size  = 0; 
 
            }else{ 
 
                //先读100个字节 
 
                data = [srcFh readDataOfLength:BUFF]; 
 
                size -= BUFF; 
 
            } 
 
            [dstFh writeData:data]; 
 
        } 
 
    } 
 
    return 0; 
 
    }