net10.0 
namespace System.Security.Permissions
{
    [AttributeUsage(AttributeTargets.Assembly | AttributeTargets.Class | AttributeTargets.Struct | AttributeTargets.Constructor | AttributeTargets.Method, AllowMultiple = true, Inherited = false)]
    [Obsolete("Code Access Security is not supported or honored by the runtime.", DiagnosticId = "SYSLIB0003", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
    public sealed class ReflectionPermissionAttribute : CodeAccessSecurityAttribute
    {
        [Obsolete("ReflectionPermissionAttribute.ReflectionEmit has been deprecated and is not supported.")]
        public bool ReflectionEmit { get; set; }
    }
}
.NET
5.06.07.08.09.010.0
.NET Core
3.03.1
.NET Framework
2.03.54.04.54.5.14.5.24.64.6.14.6.24.74.7.14.7.24.84.8.1
Information specific to net10.0
Assembly

System.Security.Permissions , Version=10.0.0.0, PublicKeyToken=cc7b13ffcd2ddd51

Referencing

Your project needs a package reference to System.Security.Permissions.

Package System.Security.Permissions (10.0.1) net10.0
Obsolete ReflectionPermissionAttribute.ReflectionEmit has been deprecated and is not supported.
Platform Restrictions

The property getter is supported on all platforms.

The property setter is supported on all platforms.

  • Built-in API
  • Package-provided API