将NSArray的字节值转换为NSData

Question

我有一个从包含字节值的Web服务返回的数组（非二进制格式，即0-255）。这些代表缩略图。我想要从这些值创建一个NSData对象。我怎么能这样做？

Answer 1

+ (id)dataWithBytes:(const void *)bytes length:(NSUInteger)length是你的朋友：

void bytesToNSDataExample() {
    unsigned char bytes[] = {'h', 'e', 'l', 'l', 'o'};
    NSData *data = [NSData dataWithBytes:bytes length:5];

    NSString *string = [[NSString alloc] initWithData:data encoding:NSISOLatin1StringEncoding];
    NSLog(@"%@", string);

    // if data was a image like in your case, you would probably do something like this:
    NSImageRep *imgRep = [NSBitmapImageRep imageRepWithData:data];
}