这样判断应该行吧:

msClipTimeNow = GetTickCount();
bool isRemove;

isRemove = false;
if ( msClipTimeNow > msExpiresTicks )
{
if (
( msCacheClipTime < msClipTimeNow - msExpiresTicks ) ||
( msCacheClipTime > msClipTimeNow ) )
{
isRemove = true;
}
}
else
{
if (
( msCacheClipTime < msClipTimeNow - msExpiresTicks ) &&
( msCacheClipTime > msClipTimeNow ) )
{
isRemove = true;
}
}