將NSArray的字節值轉換爲NSData

Question

我有一個從包含字節值（非二進制格式，即0-255）的Web服務返回的數組。這些代表縮略圖。我想需要從這些值創建一個NSData對象。我怎樣才能做到這一點？

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]; 
}