asdf.cs

    public static void ImportFile(string file) {
        string filenameWithoutExtension = Path.GetFileNameWithoutExtension(file);

        GameObject part = OlImportFile(file);

        if (null == part) {
            return;
        }

        part.name = filenameWithoutExtension;

        Mesh m = part.GetComponent<MeshFilter>().sharedMesh;
        MeshRenderer mr = part.GetComponent<MeshRenderer>();

        // save the folder and make it visible.
        AssetDatabase.SaveAssets();
        AssetDatabase.Refresh();

        Material[] meshMaterials = mr.sharedMaterials;

        for (int i = 0; i < meshMaterials.Length; i++) {
            string materialName = ((int)(meshMaterials[i].color.r * 255f)).ToString("X2")
                                + ((int)(meshMaterials[i].color.g * 255f)).ToString("X2")
                                + ((int)(meshMaterials[i].color.b * 255f)).ToString("X2")
                                + ((int)(meshMaterials[i].color.a * 255f)).ToString("X2");

            Debug.Log("Looking for Material: " + "Assets/Imported/Materials/" + materialName);

            var existingMaterial = (Material)AssetDatabase.LoadAssetAtPath("Assets/Imported/Materials/" + materialName, typeof(Material));

            if (existingMaterial != null) {
                Debug.Log("Found a matching material.");
                meshMaterials[i] = existingMaterial;
            } else {
                meshMaterials[i].enableInstancing = true;

                AssetDatabase.CreateAsset(meshMaterials[i], "Assets/Imported/Materials/" + materialName + ".mat");
            }

            AssetDatabase.SaveAssets();
            AssetDatabase.Refresh();
        }

        AssetDatabase.CreateAsset(m, "Assets/Imported/Models/" + part.name + "_M" + ".asset");

        var prefab = PrefabUtility.CreateEmptyPrefab("Assets/Imported/Prefabs" + "/" + part.name + ".prefab");
        PrefabUtility.ReplacePrefab(part, prefab);

        AssetDatabase.SaveAssets();
        AssetDatabase.Refresh();
    }