SDWebImage清理缓存
[[SDImageCache sharedImageCache] getSize]//计算缓存的大小,单位B
float tmpSize = [[SDImageCache sharedImageCache] checkTmpSize];
NSString *clearCacheName = tmpSize >= 1 ? [NSString stringWithFormat:@"清理缓存(%.2fM)",tmpSize] : [NSString stringWithFormat:@"清理缓存(%.2fK)",tmpSize * 1024];
//清理缓存
[[SDImageCache sharedImageCache] clearDisk];
[[SDImageCache sharedImageCache]clearMemory];//这一句可要可不要