Why BuildAssetBundles return null per

[gaojc915]

Why BuildAssetBundles return null after follow the instruction ?

Unity - Scripting API: BuildPipeline.BuildAssetBundles

details:
The first time, BuildAssetBundles calling generated a valid assetBundle.
Then I deleted the dir where the assetBundle is placed.
Then the second calling of BuildAssetBundles return null.

I have dived in this problem for 2 days, but no idea.
Can someone tell me why ?
Thanks for your suggestions.

[JeffDUnity3D]

@gaojc915

Why BuildAssetBundles return null after follow the instruction ?
https://docs.unity3d.com/ScriptReference/BuildPipeline.BuildAssetBundles.html

details:
The first time, BuildAssetBundles calling generated a valid assetBundle.
Then I deleted the dir where the assetBundle is placed.
Then the second calling of BuildAssetBundles return null.

I have dived in this problem for 2 days, but no idea.
Can someone tell me why ?
Thanks for your suggestions.

You deleted the entire directory? The docs say “The folder will not be created automatically and the function will simply fail if it doesn’t already exist.”