我在.mm文件中运行以下代码,我收到错误:
Invalid conversion from 'const void*' to 'const __CFData*'
我需要在.mm中运行代码。如果我改为.m,它就不会抱怨。它为什么会这样?我编译到iPhone
CFSocketNativeHandle native;
CFDataRef nativeProp = CFReadStreamCopyProperty(theReadStream, kCFStreamPropertySocketNativeHandle);
if(nativeProp == NULL)
{
if (errPtr) *errPtr = [self getStreamError];
return NO;
}
CFIndex nativePropLen = CFDataGetLength(nativeProp);
CFIndex nativeLen = (CFIndex)sizeof(native);
CFIndex len = MIN(nativePropLen, nativeLen);
CFDataGetBytes(nativeProp, CFRangeMake(0, len), (UInt8 *)&native);
CFRelease(nativeProp);
CFSocketRef theSocket = CFSocketCreateWithNative(kCFAllocatorDefault, native, 0, NULL, NULL);
if(theSocket == NULL)
{
if (errPtr) *errPtr = [self getSocketError];
return NO;
}
答案 0 :(得分:5)
CFReadStreamCopyProperty()
返回CFTypeRef
,typedef
只是const void*
,而C ++对转化的反应比C(或Objective-C)更严格。你需要在这里明确地投射:
CFDataRef nativeProp = (CFDataRef)CFReadStreamCopyProperty(...);