ResourceDictionaryExtension

Available Extensions
AddIfNotNull
RemoveIfNotNull
InsertOrReplace
RemoveAll
InsertIfNotExists
Swap

Example

mergedDictionary.AddIfNotNull(resourceDictionary);

//

mergedDictionary.RemoveIfNotNull(resourceDictionary);

//

mergedDictionary.InsertOrReplace(index, resourceDictionary);

//

mergedDictionary.InsertIfNotExists(index, resourceDictionary);

//

mergedDictionary.RemoveAll();

//

mergedDictionary.Swap(index1, index2);

Demo

you can run demo and see this feature.