Added method to SDWebImageManager to check if an image exists in either the disk OR the memory cache

SDWebImage/SDWebImageManager.h

@@ -190,6 +190,7 @@ SDWebImageManager *manager = [SDWebImageManager sharedManager];
 /**
  * Check if image has already been cached
  */
+- (BOOL)cachedImageExistsForURL:(NSURL *)url;
 - (BOOL)diskImageExistsForURL:(NSURL *)url;
 
 @end

SDWebImage/SDWebImageManager.m

@@ -60,6 +60,12 @@
     }
 }
 
+- (BOOL)cachedImageExistsForURL:(NSURL *)url {
+    NSString *key = [self cacheKeyForURL:url];
+    if ([self.imageCache imageFromMemoryCacheForKey:key] != nil) return YES;
+    return [self.imageCache diskImageExistsWithKey:key];
+}
+
 - (BOOL)diskImageExistsForURL:(NSURL *)url {
     NSString *key = [self cacheKeyForURL:url];
     return [self.imageCache diskImageExistsWithKey:key];