NSData 轉 bytes 字節數據

NSData 轉 bytes 字節數據

NSData *data = [NSData dataWithContentsOfFile:filePath];
NSUInteger len = [data length];
Byte *byteData = (Byte*)malloc(len);
memcpy(byteData, [data bytes], len);

    NSString *strPath = @"/Users/user/Desktop/jkk.txt";
    NSLog(@"string = %@",[[NSString alloc]initWithContentsOfFile:strPath encoding:NSUTF8StringEncoding error:Nil]);
    NSData *strData = [[NSData alloc]initWithContentsOfFile:strPath];
    NSLog(@"size = %d字節; strData = %@",strData.length,strData.description);
    
    NSUInteger len = [strData length];
    Byte *byteData = (Byte*)malloc(len);
    memcpy(byteData, [strData bytes], len);
    
    for (int i = 0; i < len; i++) {
        printf("%c",byteData[i]);
    }
    
    
    NSData *Data222 = [[NSData alloc]initWithBytes:byteData length:len];
    NSLog(@"Data222 : %@",Data222);
    
    NSRange rangeData = {0,3};
    NSData *subData = [strData subdataWithRange:rangeData];
    NSLog(@"subData : %@",subData);
    
    NSData *Data333 = [[NSData alloc]initWithData:subData];
    NSLog(@"Data333: %@",[[NSString alloc]initWithData:Data333 encoding:NSUTF8StringEncoding]);

result 

參考：http://stackoverflow.com/questions/724086/how-to-convert-nsdata-to-byte-array-in-iphone