如何将CFDataRef转换为NSData？

Question

如何将CFDataRef转换为NSData？

我有CFDataRef,我想将其转换为NSData.我没有得到如何做到这一点.

有人帮我..

    CGDataProviderRef dataProvider = CGImageGetDataProvider(screenShot);
    CFDataRef data = CGDataProviderCopyData(dataProvider);
    CGDataProviderRelease(dataProvider);
    NSString *imagePathLocation = [destinationPath stringByAppendingString:[@"/" stringByAppendingString:DesktopImage]];
    [[NSFileManager defaultManager]createFileAtPath: imagePathLocation contents:nil attributes:nil];
    fileHandleForImage = [NSFileHandle fileHandleForWritingAtPath:imagePathLocation];
    NSData * data1 = (NSData *)data;
    [fileHandleForImage writeData:data1];

当我进行类型转换(NSData * data1 = (NSData *)data)时,它会被图像损坏.

Answer 1

这是免费的桥接,所以你只需要施放它.

NSData *myData = (NSData *)myCFDataRef;

Answer 2

正如@KrisMarkel所说,你只需要将所有权转移给ARC,如下所示:

像这样转让所有权:

NSData* data1 = (__bridge_transfer NSData*) data;

否则在不转让所有权的情况下使用参考:

NSData* data2 = (__bridge NSData*) data;