Activator.cs

Go to the documentation of this file.

using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Reflection;
using System.Reflection.Emit;
using System.Runtime.CompilerServices;
using System.Runtime.Loader;
using System.Runtime.Remoting;
using System.Threading;
 
namespace System;
 
public static class Activator
{
    [DebuggerHidden]
    [DebuggerStepThrough]
    public static object? CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors)] Type type, BindingFlags bindingAttr, Binder? binder, object?[]? args, CultureInfo? culture)
    {
        return CreateInstance(type, bindingAttr, binder, args, culture, null);
    }
 
    [DebuggerHidden]
    [DebuggerStepThrough]
    public static object? CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)] Type type, params object?[]? args)
    {
        return CreateInstance(type, BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance, null, args, null, null);
    }
 
    [DebuggerHidden]
    [DebuggerStepThrough]
    public static object? CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)] Type type, object?[]? args, object?[]? activationAttributes)
    {
        return CreateInstance(type, BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance, null, args, null, activationAttributes);
    }
 
    [DebuggerHidden]
    [DebuggerStepThrough]
    public static object? CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)] Type type)
    {
        return CreateInstance(type, nonPublic: false);
    }
 
    [RequiresUnreferencedCode("Type and its constructor could be removed")]
    public static ObjectHandle? CreateInstanceFrom(string assemblyFile, string typeName)
    {
        return CreateInstanceFrom(assemblyFile, typeName, ignoreCase: false, BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance, null, null, null, null);
    }
 
    [RequiresUnreferencedCode("Type and its constructor could be removed")]
    public static ObjectHandle? CreateInstanceFrom(string assemblyFile, string typeName, object?[]? activationAttributes)
    {
        return CreateInstanceFrom(assemblyFile, typeName, ignoreCase: false, BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance, null, null, null, activationAttributes);
    }
 
    [RequiresUnreferencedCode("Type and its constructor could be removed")]
    public static ObjectHandle? CreateInstanceFrom(string assemblyFile, string typeName, bool ignoreCase, BindingFlags bindingAttr, Binder? binder, object?[]? args, CultureInfo? culture, object?[]? activationAttributes)
    {
        Assembly assembly = Assembly.LoadFrom(assemblyFile);
        Type type = assembly.GetType(typeName, throwOnError: true, ignoreCase);
        object obj = CreateInstance(type, bindingAttr, binder, args, culture, activationAttributes);
        if (obj == null)
        {
            return null;
        }
        return new ObjectHandle(obj);
    }
 
    public static object? CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors)] Type type, BindingFlags bindingAttr, Binder? binder, object?[]? args, CultureInfo? culture, object?[]? activationAttributes)
    {
        if ((object)type == null)
        {
            throw new ArgumentNullException("type");
        }
        if (type is TypeBuilder)
        {
            throw new NotSupportedException(SR.NotSupported_CreateInstanceWithTypeBuilder);
        }
        if ((bindingAttr & (BindingFlags)255) == 0)
        {
            bindingAttr |= BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance;
        }
        if (activationAttributes != null && activationAttributes.Length != 0)
        {
            throw new PlatformNotSupportedException(SR.NotSupported_ActivAttr);
        }
        if (type.UnderlyingSystemType is RuntimeType runtimeType)
        {
            return runtimeType.CreateInstanceImpl(bindingAttr, binder, args, culture);
        }
        throw new ArgumentException(SR.Arg_MustBeType, "type");
    }
 
    [RequiresUnreferencedCode("Type and its constructor could be removed")]
    public static ObjectHandle? CreateInstance(string assemblyName, string typeName)
    {
        StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
        return CreateInstanceInternal(assemblyName, typeName, ignoreCase: false, BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance, null, null, null, null, ref stackMark);
    }
 
    [RequiresUnreferencedCode("Type and its constructor could be removed")]
    public static ObjectHandle? CreateInstance(string assemblyName, string typeName, bool ignoreCase, BindingFlags bindingAttr, Binder? binder, object?[]? args, CultureInfo? culture, object?[]? activationAttributes)
    {
        StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
        return CreateInstanceInternal(assemblyName, typeName, ignoreCase, bindingAttr, binder, args, culture, activationAttributes, ref stackMark);
    }
 
    [RequiresUnreferencedCode("Type and its constructor could be removed")]
    public static ObjectHandle? CreateInstance(string assemblyName, string typeName, object?[]? activationAttributes)
    {
        StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
        return CreateInstanceInternal(assemblyName, typeName, ignoreCase: false, BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance, null, null, null, activationAttributes, ref stackMark);
    }
 
    public static object? CreateInstance([DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors)] Type type, bool nonPublic)
    {
        return CreateInstance(type, nonPublic, wrapExceptions: true);
    }
 
    internal static object CreateInstance(Type type, bool nonPublic, bool wrapExceptions)
    {
        if ((object)type == null)
        {
            throw new ArgumentNullException("type");
        }
        if (!(type.UnderlyingSystemType is RuntimeType runtimeType))
        {
            throw new ArgumentException(SR.Arg_MustBeType, "type");
        }
        return runtimeType.CreateInstanceDefaultCtor(!nonPublic, wrapExceptions);
    }
 
    [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2026:RequiresUnreferencedCode", Justification = "Implementation detail of Activator that linker intrinsically recognizes")]
    [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2072:UnrecognizedReflectionPattern", Justification = "Implementation detail of Activator that linker intrinsically recognizes")]
    [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2096:UnrecognizedReflectionPattern", Justification = "Implementation detail of Activator that linker intrinsically recognizes")]
    private static ObjectHandle CreateInstanceInternal(string assemblyString, string typeName, bool ignoreCase, BindingFlags bindingAttr, Binder binder, object[] args, CultureInfo culture, object[] activationAttributes, ref StackCrawlMark stackMark)
    {
        Assembly assembly;
        if (assemblyString == null)
        {
            assembly = Assembly.GetExecutingAssembly(ref stackMark);
        }
        else
        {
            AssemblyName assemblyName = new AssemblyName(assemblyString);
            assembly = RuntimeAssembly.InternalLoad(assemblyName, ref stackMark, AssemblyLoadContext.CurrentContextualReflectionContext);
        }
        Type type = assembly.GetType(typeName, throwOnError: true, ignoreCase);
        object obj = CreateInstance(type, bindingAttr, binder, args, culture, activationAttributes);
        if (obj == null)
        {
            return null;
        }
        return new ObjectHandle(obj);
    }
 
    [Intrinsic]
    public static T CreateInstance<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)] T>()
    {
        return (T)((RuntimeType)typeof(T)).CreateInstanceOfT();
    }
 
    private static T CreateDefaultInstance<T>() where T : struct
    {
        return default(T);
    }
}