internal static extern JavaScriptErrorCode JsHasProperty(JavaScriptValue obj, JavaScriptPropertyId propertyId, out bool hasProperty);

 internal static extern JavaScriptErrorCode JsGetOwnPropertyDescriptor(JavaScriptValue obj, JavaScriptPropertyId propertyId, out JavaScriptValue propertyDescriptor);

 internal static extern JavaScriptErrorCode JsSetProperty(JavaScriptValue obj, JavaScriptPropertyId propertyId, JavaScriptValue value, bool useStrictRules);

 internal static extern JavaScriptErrorCode JsGetPropertyNameFromId(JavaScriptPropertyId propertyId, out string name);

 internal static extern JavaScriptErrorCode JsGetProperty(JavaScriptValue obj, JavaScriptPropertyId propertyId, out JavaScriptValue value);

 /// <summary>
 ///     Gets a property descriptor for an object's own property.
 /// </summary>
 /// <remarks>
 ///     Requires an active script context.
 /// </remarks>
 /// <param name="propertyId">The ID of the property.</param>
 /// <returns>The property descriptor.</returns>
 public JavaScriptValue GetOwnPropertyDescriptor(JavaScriptPropertyId propertyId)
 {
     JavaScriptValue descriptorReference;
     Native.ThrowIfError(Native.JsGetOwnPropertyDescriptor(this, propertyId, out descriptorReference));
     return descriptorReference;
 }

 internal static extern JavaScriptErrorCode JsGetPropertyIdFromName(string name, out JavaScriptPropertyId propertyId);

 internal static extern JavaScriptErrorCode JsGetPropertyIdType(JavaScriptPropertyId propertyId, out JavaSciptPropertyIdType propertyIdType);

 internal static extern JavaScriptErrorCode JsGetSymbolFromPropertyId(JavaScriptPropertyId propertyId, out JavaScriptValue symbol);

 /// <summary>
 ///     Deletes an object's property.
 /// </summary>
 /// <remarks>
 ///     Requires an active script context.
 /// </remarks>
 /// <param name="propertyId">The ID of the property.</param>
 /// <param name="useStrictRules">The property set should follow strict mode rules.</param>
 /// <returns>Whether the property was deleted.</returns>
 public JavaScriptValue DeleteProperty(JavaScriptPropertyId propertyId, bool useStrictRules)
 {
     JavaScriptValue returnReference;
     Native.ThrowIfError(Native.JsDeleteProperty(this, propertyId, useStrictRules, out returnReference));
     return returnReference;
 }

 /// <summary>
 ///     Defines a new object's own property from a property descriptor.
 /// </summary>
 /// <remarks>
 ///     Requires an active script context.
 /// </remarks>
 /// <param name="propertyId">The ID of the property.</param>
 /// <param name="propertyDescriptor">The property descriptor.</param>
 /// <returns>Whether the property was defined.</returns>
 public bool DefineProperty(JavaScriptPropertyId propertyId, JavaScriptValue propertyDescriptor)
 {
     bool result;
     Native.ThrowIfError(Native.JsDefineProperty(this, propertyId, propertyDescriptor, out result));
     return result;
 }

 /// <summary>
 ///     Sets an object's property.
 /// </summary>
 /// <remarks>
 ///     Requires an active script context.
 /// </remarks>
 /// <param name="id">The ID of the property.</param>
 /// <param name="value">The new value of the property.</param>
 /// <param name="useStrictRules">The property set should follow strict mode rules.</param>
 public void SetProperty(JavaScriptPropertyId id, JavaScriptValue value, bool useStrictRules)
 {
     Native.ThrowIfError(Native.JsSetProperty(this, id, value, useStrictRules));
 }

 /// <summary>
 ///     Gets an object's property.
 /// </summary>
 /// <remarks>
 ///     Requires an active script context.
 /// </remarks>
 /// <param name="id">The ID of the property.</param>
 /// <returns>The value of the property.</returns>
 public JavaScriptValue GetProperty(JavaScriptPropertyId id)
 {
     JavaScriptValue propertyReference;
     Native.ThrowIfError(Native.JsGetProperty(this, id, out propertyReference));
     return propertyReference;
 }

 /// <summary>
 ///     Determines whether an object has a property.
 /// </summary>
 /// <remarks>
 ///     Requires an active script context.
 /// </remarks>
 /// <param name="propertyId">The ID of the property.</param>
 /// <returns>Whether the object (or a prototype) has the property.</returns>
 public bool HasProperty(JavaScriptPropertyId propertyId)
 {
     bool hasProperty;
     Native.ThrowIfError(Native.JsHasProperty(this, propertyId, out hasProperty));
     return hasProperty;
 }

 internal static extern JavaScriptErrorCode JsDeleteProperty(JavaScriptValue obj, JavaScriptPropertyId propertyId, bool useStrictRules, out JavaScriptValue result);

 internal static extern JavaScriptErrorCode JsGetPropertyIdFromSymbol(JavaScriptValue symbol, out JavaScriptPropertyId propertyId);

 internal static extern JavaScriptErrorCode JsDefineProperty(JavaScriptValue obj, JavaScriptPropertyId propertyId, JavaScriptValue propertyDescriptor, out bool result);

 internal static extern JavaScriptErrorCode JsGetPropertyNameFromId(JavaScriptPropertyId propertyId, out IntPtr buffer);