# Attributes

### <span style="color: rgb(53, 152, 219);">What are attributes?</span>

Attributes are ***"markers"*** or ***"tags"*** for associating metadata with code in a declarative way. They can be used to tell the Unity Editor, C# compiler, or even our own scripts how to treat certain ***classes***, ***fields***, ***methods***, and so on.

<p class="callout info">[https://docs.unity3d.com/Manual/Attributes.html](https://docs.unity3d.com/Manual/Attributes.html)</p>

Attributes are declared right before their target and are always wrapped in brackets:

```c#
using JetBrains.Annotations;
using System.Runtime.CompilerServices;
using UdonSharp;
using UnityEngine;
using UnityEngine.Serialization;
using Varneon.VUdon.Editors;
using Varneon.VUdon.Noclip.Abstract;
using Varneon.VUdon.Noclip.Enums;
using VRC.SDKBase;
using VRC.Udon.Common;

[assembly: InternalsVisibleTo("Varneon.VUdon.Noclip.Editor")]

namespace Varneon.VUdon.Noclip
{
    [SelectionBase]
    [DefaultExecutionOrder(-1000000000)]
    [AddComponentMenu("VUdon/Noclip")]
    [DisallowMultipleComponent]
    [HelpURL("https://github.com/Varneon/VUdon-Noclip/wiki/Settings")]
    [UdonBehaviourSyncMode(BehaviourSyncMode.None)]
    public partial class Noclip : UdonSharpBehaviour
    {
        [FoldoutHeader("Options", "Options that can be edited before build and in-game")]
        [SerializeField]
        [Tooltip("Method for triggering the noclip mode")]
        private NoclipTriggerMethod noclipTriggerMethod = NoclipTriggerMethod.DoubleJump;

        [SerializeField]
        [FieldLabel("Toggle Threshold (s)")]
        [Tooltip("Time in which jump has to be double tapped in order to toggle noclip")]
        [FieldRange(0.1f, 1f)]
        private float toggleThreshold = 0.25f;

        [SerializeField]
        [FieldLabel("Speed (m/s)")]
        [Tooltip("Maximum speed in m/s")]
        [Min(1f)]
        [FormerlySerializedAs("velocity")]
        private float speed = 15f;

        [PublicAPI("Sets noclip enabled")]
        public void _SetNoclipEnabled(bool enabled)
        {
            SetNoclipEnabled(enabled);
        }

#if UNITY_EDITOR && !COMPILER_UDONSHARP
        [UsedImplicitly]
        [UnityEditor.Callbacks.PostProcessScene(-1)]
        private static void InitializeOnBuild() { }
#endif
    }
}
```

---

### <span style="color: rgb(53, 152, 219);">What attributes should I know about?</span>  


There are several quality of life attributes that everyone should know and use, and here are most of them:

#### <span style="color: rgb(53, 152, 219);">Field Attributes</span>

These attributes can be used on fields, primarily to alter their appearance in the inspector.

<table border="1" cellpadding="0" cellspacing="0" dir="ltr" id="bkmrk-%5Brange%5D-restrict-a-f" style="width: 80.4938%; height: 357.563px;"><colgroup><col style="width: 25.8065%;" width="245"></col><col style="width: 74.1935%;" width="437"></col></colgroup><tbody><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[Range]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">Range</span>\]](https://docs.unity3d.com/ScriptReference/RangeAttribute.html "https://docs.unity3d.com/ScriptReference/RangeAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Restrict a float or int variable to a specific range"}" style="height: 29.7969px;">Restrict a float or int variable to a specific range</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[Min]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">Min</span>\]](https://docs.unity3d.com/ScriptReference/MinAttribute.html "https://docs.unity3d.com/ScriptReference/MinAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Restrict a float or int variable to a specific minimum value"}" style="height: 29.7969px;">Restrict a float or int variable to a specific minimum value</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[Header]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">Header</span>\]](https://docs.unity3d.com/ScriptReference/HeaderAttribute.html "https://docs.unity3d.com/ScriptReference/HeaderAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Add a space and a header above a field in inspector"}" style="height: 29.7969px;">Add a space and a header above a field in inspector</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[TextArea]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">TextArea</span>\]](https://docs.unity3d.com/ScriptReference/TextAreaAttribute.html "https://docs.unity3d.com/ScriptReference/TextAreaAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Make string field height-flexible and scrollable"}" style="height: 29.7969px;">Make string field height-flexible and scrollable</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[ColorUsage]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">ColorUsage</span>\]](https://docs.unity3d.com/ScriptReference/ColorUsageAttribute.html "https://docs.unity3d.com/ScriptReference/ColorUsageAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Configure color field to support HDR and/or alpha"}" style="height: 29.7969px;">Configure Color field to support HDR and/or alpha</td></tr><tr><td>[\[<span style="color: rgb(22, 145, 121);">GradientUsage</span>\]](https://docs.unity3d.com/ScriptReference/GradientUsageAttribute.html "https://docs.unity3d.com/ScriptReference/GradientUsageAttribute.html")</td><td>Configure Gradient field's color space and HDR</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[Space]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">Space</span>\]](https://docs.unity3d.com/ScriptReference/SpaceAttribute.html "https://docs.unity3d.com/ScriptReference/SpaceAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Add a space above a field in inspector"}" style="height: 29.7969px;">Add a space above a field in inspector</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[SerializeField]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">SerializeField</span>\]](https://docs.unity3d.com/ScriptReference/SerializeField.html "https://docs.unity3d.com/ScriptReference/SerializeField.html")</td><td data-sheets-value="{"1":2,"2":"Force Unity to serialize a private field"}" style="height: 29.7969px;">Force Unity to serialize a private field</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[HideInInspector]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">HideInInspector</span>\]](https://docs.unity3d.com/ScriptReference/HideInInspector.html "https://docs.unity3d.com/ScriptReference/HideInInspector.html")</td><td data-sheets-value="{"1":2,"2":"Hide a variable from the inspector"}" style="height: 29.7969px;">Hide a variable from the inspector</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[Tooltip]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">Tooltip</span>\]](https://docs.unity3d.com/ScriptReference/TooltipAttribute.html "https://docs.unity3d.com/ScriptReference/TooltipAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Display a text in inspector when hovering over a field"}" style="height: 29.7969px;">Display a text in inspector when hovering over a field</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[NonSerialized]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">NonSerialized</span>\]](https://docs.unity3d.com/ScriptReference/NonSerialized.html "https://docs.unity3d.com/ScriptReference/NonSerialized.html")</td><td data-sheets-value="{"1":2,"2":"Prevent variable from being serialized (also hides from inspector)"}" style="height: 29.7969px;">Prevent variable from being serialized (also hides from inspector)</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[NonReorderable]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">NonReorderable</span>\]](https://docs.unity3d.com/ScriptReference/NonReorderableAttribute.html "https://docs.unity3d.com/ScriptReference/NonReorderableAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Disable default reorderability in new array and list fields (Unity 2020.2+)"}" style="height: 29.7969px;">Disable default reorderability in new array and list fields ***(<span style="color: rgb(35, 111, 161);">Unity 2020.2+</span>)***</td></tr><tr style="height: 29.7969px;"><td data-sheets-value="{"1":2,"2":"[FormerlySerializedAs]"}" style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">FormerlySerializedAs</span>\]](https://docs.unity3d.com/ScriptReference/Serialization.FormerlySerializedAsAttribute.html "https://docs.unity3d.com/ScriptReference/Serialization.FormerlySerializedAsAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Preserve original serialized value of a field when renaming it"}" style="height: 29.7969px;">Preserve original serialized value of a field when renaming it</td></tr></tbody></table>

#### <span style="color: rgb(53, 152, 219);">Class Attributes</span>

These attributes can be used on classes.

<table border="1" cellpadding="0" cellspacing="0" dir="ltr" id="bkmrk-%5Budonbehavioursyncmo" style="width: 95.1852%; height: 247.734px;"><colgroup><col style="width: 27.5315%;" width="245"></col><col style="width: 72.4685%;" width="528"></col></colgroup><tbody><tr style="height: 35.3906px;"><td data-sheets-value="{"1":2,"2":"[UdonBehaviourSyncMode]"}" style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">UdonBehaviourSyncMode</span>\]](https://udonsharp.docs.vrchat.com/udonsharp#udonbehavioursyncmode "https://udonsharp.docs.vrchat.com/udonsharp#udonbehavioursyncmode")</td><td data-sheets-value="{"1":2,"2":"Enforce a synchronization mode of an UdonSharpBehaviour"}" style="height: 35.3906px;">Enforce a synchronization mode of an UdonSharpBehaviour</td></tr><tr style="height: 35.3906px;"><td data-sheets-value="{"1":2,"2":"[DefaultExecutionOrder]"}" style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">DefaultExecutionOrder</span>\]](https://udonsharp.docs.vrchat.com/udonsharp#defaultexecutionorder "https://udonsharp.docs.vrchat.com/udonsharp#defaultexecutionorder")</td><td data-sheets-value="{"1":2,"2":"Specify the execution order of update loops in relation to other UdonSharpBehaviours"}" style="height: 35.3906px;">Specify the execution order of update loops in relation to other UdonSharpBehaviours</td></tr><tr style="height: 35.3906px;"><td data-sheets-value="{"1":2,"2":"[RequireComponent]"}" style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">RequireComponent</span>\]](https://docs.unity3d.com/ScriptReference/RequireComponent.html "https://docs.unity3d.com/ScriptReference/RequireComponent.html")</td><td data-sheets-value="{"1":2,"2":"Add components automatically to the same object"}" style="height: 35.3906px;">Add a component automatically to the same object and prevent its removal</td></tr><tr style="height: 35.3906px;"><td data-sheets-value="{"1":2,"2":"[DisallowMultipleComponent]"}" style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">DisallowMultipleComponent</span>\]](https://docs.unity3d.com/ScriptReference/DisallowMultipleComponent.html "https://docs.unity3d.com/ScriptReference/DisallowMultipleComponent.html")</td><td data-sheets-value="{"1":2,"2":"Prevent multiple instances of the component from being added to the same object"}" style="height: 35.3906px;">Prevent multiple instances of the component from being added to the same object</td></tr><tr style="height: 35.3906px;"><td data-sheets-value="{"1":2,"2":"[AddComponent]"}" style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">AddComponent</span>\]](https://docs.unity3d.com/ScriptReference/AddComponentMenu.html "https://docs.unity3d.com/ScriptReference/AddComponentMenu.html")</td><td data-sheets-value="{"1":2,"2":"Specify the path to this component in the \"Add Component\" menu"}" style="height: 35.3906px;">Specify the path to this component in the "Add Component" menu</td></tr><tr style="height: 35.3906px;"><td data-sheets-value="{"1":2,"2":"[ExcludeFromPreset]"}" style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">ExcludeFromPreset</span>\]](https://docs.unity3d.com/ScriptReference/ExcludeFromPresetAttribute.html "https://docs.unity3d.com/ScriptReference/ExcludeFromPresetAttribute.html")</td><td data-sheets-value="{"1":2,"2":"Prevent creation of presets from instances of the class"}" style="height: 35.3906px;">Prevent creation of presets from instances of the class</td></tr><tr style="height: 35.3906px;"><td style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">SelectionBase</span>\]](https://docs.unity3d.com/ScriptReference/SelectionBaseAttribute.html "https://docs.unity3d.com/ScriptReference/SelectionBaseAttribute.html")</td><td style="height: 35.3906px;">Mark the GameObject as a selection base object for Scene View picking</td></tr><tr><td>[\[<span style="color: rgb(22, 145, 121);">Icon</span>\]](https://docs.unity3d.com/ScriptReference/IconAttribute.html "https://docs.unity3d.com/ScriptReference/IconAttribute.html")</td><td>Specify an icon for a MonoBehaviour or ScriptableObject ***(<span style="color: rgb(35, 111, 161);">Unity 2021.3+</span>)***</td></tr></tbody></table>

#### <span style="color: rgb(53, 152, 219);">Method Attributes</span>

These attributes can be used on methods.

<table border="1" id="bkmrk-%5Bcontextmenu%5D-add-a-" style="border-collapse: collapse; width: 60.9877%; height: 29.7969px;"><colgroup><col style="width: 29.0875%;"></col><col style="width: 70.9125%;"></col></colgroup><tbody><tr style="height: 29.7969px;"><td style="height: 29.7969px;">[\[<span style="color: rgb(22, 145, 121);">ContextMenu</span>\]](https://docs.unity3d.com/ScriptReference/ContextMenu.html "https://docs.unity3d.com/ScriptReference/ContextMenu.html")</td><td style="height: 29.7969px;">Add a command to the Component's context menu</td></tr></tbody></table>

#### <span style="color: rgb(53, 152, 219);">Common Attributes</span>

<table border="1" id="bkmrk-%5Bobsolete%5D-mark-an-e" style="border-collapse: collapse; width: 87.4074%; height: 106.172px;"><colgroup><col style="width: 20.4451%;"></col><col style="width: 79.5549%;"></col></colgroup><tbody><tr style="height: 35.3906px;"><td style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">Obsolete</span>\]](https://learn.microsoft.com/en-us/dotnet/api/system.obsoleteattribute?view=net-7.0 "https://learn.microsoft.com/en-us/dotnet/api/system.obsoleteattribute?view=net-7.0")</td><td style="height: 35.3906px;">Mark an element to be no longer in use</td></tr><tr style="height: 35.3906px;"><td style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">PublicAPI</span>\]](https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#PublicAPIAttribute "https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#PublicAPIAttribute")</td><td style="height: 35.3906px;">Mark publicly available API which should not be removed and treated as used</td></tr><tr style="height: 35.3906px;"><td style="height: 35.3906px;">[\[<span style="color: rgb(22, 145, 121);">UsedImplicitly</span>\]](https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#UsedImplicitlyAttribute "https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#UsedImplicitlyAttribute")</td><td style="height: 35.3906px;">Indicates that the marked symbol is used implicitly (e.g. via reflection, in external library)</td></tr><tr><td>[\[<span style="color: rgb(22, 145, 121);">NotNull</span>\]](https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#NotNullAttribute "https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#NotNullAttribute")</td><td>Indicates that the value of the marked element can never be null</td></tr><tr><td>[\[<span style="color: rgb(22, 145, 121);">CanBeNull</span>\]](https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#CanBeNullAttribute "https://www.jetbrains.com/help/resharper/Reference__Code_Annotation_Attributes.html#CanBeNullAttribute")</td><td>Indicates that the value of the marked element could be null sometimes</td></tr></tbody></table>

#### <span style="color: rgb(53, 152, 219);">Other Attributes</span>

These attributes don't fall into the categories above, but are extremely useful and commonly used.

---

##### [\[<span style="color: rgb(22, 145, 121);">InternalsVisibleTo</span>\]](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.internalsvisibletoattribute?view=net-7.0 "https://learn.microsoft.com/en-us/dotnet/api/system.runtime.compilerservices.internalsvisibletoattribute?view=net-7.0")

This attribute allows you to make your Runtime assembly's [internal](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/internal "https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/internal") members visible to the Editor assembly.

<p class="callout info">Example of this attribute being used: [Udonity's AssemblyInfo.cs](https://github.com/Varneon/VUdon-Udonity/blob/main/Packages/com.varneon.vudon.udonity/Runtime/AssemblyInfo.cs "https://github.com/Varneon/VUdon-Udonity/blob/main/Packages/com.varneon.vudon.udonity/Runtime/AssemblyInfo.cs")</p>

1. Create a new C# file called `AssemblyInfo.cs` into your Runtime folder
2. Add the following content inside the file: ```c#
    using System.Runtime.CompilerServices;
    [assembly: InternalsVisibleTo("YOUR_EDITOR_ASSEMBLY_NAME_HERE")]
    ```

---

##### [\[<span style="color: rgb(22, 145, 121);">CreateAssetMenu</span>\]](https://docs.unity3d.com/ScriptReference/CreateAssetMenuAttribute.html "https://docs.unity3d.com/ScriptReference/CreateAssetMenuAttribute.html")

Mark a [ScriptableObject](https://docs.unity3d.com/ScriptReference/ScriptableObject.html "https://docs.unity3d.com/ScriptReference/ScriptableObject.html")-derived type to be automatically listed in the Assets/Create submenu.

Learn more about ScriptableObjects [here](https://vrclibrary.com/wiki/books/varneons-unity-development-handbook/page/scriptable-objects "https://vrclibrary.com/wiki/books/varneons-unity-development-handbook/page/scriptable-objects").

```c#
// menuName: Path to the menu item
// fileName: Default name of the new file
// order: Priority of the menu item (100 is often reasonble)
[CreateAssetMenu(menuName = "VUdon - Vehicles/Data Presets/Car Spec Sheet", fileName = "NewCarSpecSheet.asset", order = 100)]
public class CarSpecSheet : ScriptableObject { }
```

---

##### [\[<span style="color: rgb(22, 145, 121);">InspectorName</span>\]](https://docs.unity3d.com/ScriptReference/InspectorNameAttribute.html "https://docs.unity3d.com/ScriptReference/InspectorNameAttribute.html")

Use this attribute on enum value declarations to change the display name shown in the Inspector.

```c#
public enum ColorDisplayMode
{
    [InspectorName("RGB 0-255")]
    RGB255,

    [InspectorName("RGB 0-1.0")]
    RGB1,

    HSV
}
```