Which Assets Are Included In An Asset Bundle?  (Unity)

Symptoms

• You found that some Asset bundles are larger than expected.
• You need to know what is packed into the Asset bundle.

Cause

If you have an Asset marked as none in the Inspector bundle name but other Assets have a dependency on it, it will be included in the bundle.

This will cause repeated Assets in AssetBundles.

Resolution

The simple way to inspect an Asset bundle is to create a public Asset bundle variable. Load the Asset bundle and double-click the Asset bundle object in the Inspector to open the Inspector with the content of the Asset bundle.

You now have a list of the elements that include the Asset bundle and a list of their dependencies.

Example:

public AssetBundle assetBundle;

Double-click on the cube bar in the Inspector window to view the bundle’s properties.

Another alternative is to use an Editor script to load the Asset bundle as a SerializedObject and iterate for all the elements of the object.

[MenuItem("SUPPORT/Bundles/Print Contents")]
    static void PrintContents()
    {
        if( Selection.activeObject == null )
            return;

        AssetBundle bundle = AssetBundle.LoadFromFile( Application.dataPath + AssetDatabase.GetAssetPath( Selection.activeObject ).Remove(0,6) );

        if( bundle != null )
        {
            SerializedObject so = new SerializedObject( bundle );
            System.Text.StringBuilder str = new System.Text.StringBuilder();

            str.Append( "Preload table:n" );
            foreach( SerializedProperty d in so.FindProperty( "m_PreloadTable" ) )
            {
                if( d.objectReferenceValue != null )
                    str.Append( "t<color=green>" + d.objectReferenceValue.name + " " + d.objectReferenceValue.GetType().ToString() + "n" );
            }

            str.Append( "Container:n" );
            foreach( SerializedProperty d in so.FindProperty( "m_Container" ) )
                str.Append( "t" + d.displayName + "n" );

            Debug.Log( str.ToString() );
            bundle.Unload( false );
        }

Additionally, you can check the Editor log after you build the Asset bundles.