unity how to check collider layer against list of layer mask with list code example

Example 1: Check object is in layermask unity

public bool IsInLayerMask(GameObject obj, LayerMask layerMask)
{
	return ((layerMask.value & (1 << obj.layer)) > 0);
}

Example 2: collider layer = to layermask unity

layermask == (layermask | (1 << layer))