# SetPropertyModifications(Object, PropertyModification[])

> Assigns a set of PropertyModification objects to a target Prefab instance relative to its source Prefab Asset.

## Definition

* **Type:** Method
* **Namespace:** [UnityEditor](/engine/6000.7/script-reference/unityeditor.md)
* **Assembly:** UnityEditor.CoreModule

```csharp
public static void SetPropertyModifications(Object targetPrefab, PropertyModification[] modifications)
```

### Parameters

**** (\[Object]\(/engine/6000.7/script-reference/unityengine/object)): A reference to the Prefab instance to be modified. Although the type and name imply an asset, it is the outermost instance as a GameObject that should be provided.**** (\[PropertyModification\[]]\(/engine/6000.7/script-reference/unityeditor/propertymodification)): A set of PropertyModification objects that define the changes to the target Prefab instance.

### Remarks

It's important to provide this method with the top-level object in the target instance's branch of the hierarchy to avoid unexpected results. Use [GetOutermostPrefabInstanceRoot](/engine/6000.7/script-reference/unityeditor/prefabutility/getoutermostprefabinstanceroot.md) for this purpose.

[PropertyModification](/engine/6000.7/script-reference/unityeditor/propertymodification.md) fields for Prefab overrides:

* **target**: A persistent Prefab asset object reference

* **propertyPath**: The path of the property to be modified

* **value**: The value of the property as a string

* **objectReference**: Set this field if the modification is an object reference, otherwise set the `value` field

The PropertyModification members always expected to have been set are the `target` object the modification applies to (i.e. a persistent Prefab asset object reference), the `propertyPath` of the property to be modified and its new `value` or `objectReference`, as shown in the following example:

```csharp
void MakePrefabModifications(GameObject gameObject)
{
    // Get the outermost root from the target object
    GameObject prefabInstanceRoot = PrefabUtility.GetOutermostPrefabInstanceRoot(gameObject);
    if (prefabInstanceRoot == null)
        return;

    // Get the corresponding prefab asset
    GameObject prefabAssetRoot = PrefabUtility.GetCorrespondingObjectFromSource(prefabInstanceRoot);

    // Create modifications for m_Name and m_LocalScale.x
    var mods = new[]
    {
        new UnityEditor.PropertyModification { value = "NewName", propertyPath = "m_Name", target = prefabAssetRoot },
        new UnityEditor.PropertyModification { value = "3", propertyPath = "m_LocalScale.x", target = prefabAssetRoot.transform }
    };

    PrefabUtility.SetPropertyModifications(prefabInstanceRoot, mods);
}
```

The following example shows an example of /PropertyModification.objectReference/ usage on a Prefab which has a MeshRenderer:

```csharp
void MakePrefabModificationUsingObjectReference(GameObject gameObject)
{
    // Get the outermost root from the target object
    GameObject prefabInstanceRoot = PrefabUtility.GetOutermostPrefabInstanceRoot(gameObject);
    if (prefabInstanceRoot == null)
        return;

    // Get the corresponding prefab asset
    GameObject prefabAssetRoot = PrefabUtility.GetCorrespondingObjectFromSource(prefabInstanceRoot);

    MeshRenderer prefabMeshRenderer = prefabAssetRoot.GetComponent<MeshRenderer>();

    // Create a material asset to add to the MeshRenderer
    Material material = new Material(Shader.Find("Diffuse"));
    AssetDatabase.CreateAsset(material, "Assets/MyMaterial.mat");

    var mods = new[]
    {
        new UnityEditor.PropertyModification { target = prefabMeshRenderer, propertyPath = "m_Materials.Array.data[0]", objectReference = material }
    };

    PrefabUtility.SetPropertyModifications(prefabInstanceRoot, mods);
}
```

Be aware that calls to `SetPropertyModifications` will replace the previous set of modifications. If the intention is to accumulate modifications, then retrieve the current set with [GetPropertyModifications](/engine/6000.7/script-reference/unityeditor/prefabutility/getpropertymodifications.md) and include them in the new set.

SetPropertyModifications can be used to remove unwanted modifications. To remove only non-default modifications, filter them away and keep the default overrides, as below:

```csharp
List<PropertyModification> defaultMods = new List<PropertyModification>();
PropertyModification[] mods = PrefabUtility.GetPropertyModifications(prefabInstanceRoot);
foreach (var mod in mods)
{
    if (PrefabUtility.IsDefaultOverride(mod))
        defaultMods.Add(mod);
}

PrefabUtility.SetPropertyModifications(prefabInstanceRoot, defaultMods.ToArray());
```

For creating overrides a preferred approach is to use either [RecordPrefabInstancePropertyModifications](/engine/6000.7/script-reference/unityeditor/prefabutility/recordprefabinstancepropertymodifications.md) for manually changed properties or use [SerializedObject](/engine/6000.7/script-reference/unityeditor/serializedobject.md) and [SerializedProperty](/engine/6000.7/script-reference/unityeditor/serializedproperty.md) which will automatically generate overrides.

For applying and reverting overrides consider using the following API which provide convenient access to Apply and Revert functionality:

[GetObjectOverrides](/engine/6000.7/script-reference/unityeditor/prefabutility/getobjectoverrides.md) [GetAddedComponents](/engine/6000.7/script-reference/unityeditor/prefabutility/getaddedcomponents.md) [GetRemovedComponents](/engine/6000.7/script-reference/unityeditor/prefabutility/getremovedcomponents.md) [GetAddedGameObjects](/engine/6000.7/script-reference/unityeditor/prefabutility/getaddedgameobjects.md) [GetRemovedGameObjects](/engine/6000.7/script-reference/unityeditor/prefabutility/getremovedgameobjects.md).