Meziantou.Polyfill

Name: Meziantou.Polyfill
Availability: InStock
Author: meziantou

v1.0.50

.NETStandard2.0

Source Generator to help multi-targeting projects.

meziantou

NuGet Website MITCompare

Published

Sep 9, 2025

1y ago

Total Downloads

685.5K

685,519

Install

dotnet add package Meziantou.Polyfill --version 1.0.50

Download NuGet File Browse File Contents

Product	Versions
.NET Standard	netstandard2.0

README

Meziantou.Polyfill

Source Generator that adds polyfill methods and types. This helps working with multi-targeted projects.

Read more about the project: Polyfills in .NET to ease multi-targeting

Installation

dotnet add package Meziantou.Polyfill

Then, you should see the generated types in the solution explorer

Generated files in the Visual Studio's Solution Explorer

Customization

By default, all needed polyfills are generated. You can configure which polyfills should be generated by editing the .csproj file and adding the following properties:

<PropertyGroup>
  <!-- semicolon-separated or pipe-separated list of name prefix -->
  <!-- Tip: The name of the generated polyfills are available in the generated "Debug.g.cs" file -->
  <MeziantouPolyfill_IncludedPolyfills>T:Type1|T:Type2|M:Member1</MeziantouPolyfill_IncludedPolyfills>
  <MeziantouPolyfill_ExcludedPolyfills>M:System.Diagnostics.</MeziantouPolyfill_ExcludedPolyfills>

  <!-- Optional: Output the generated files to the obj\GeneratedFiles folder  -->
  <EmitCompilerGeneratedFiles>True</EmitCompilerGeneratedFiles>
  <CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GeneratedFiles</CompilerGeneratedFilesOutputPath>
</PropertyGroup>

Supported polyfills

Types

System.Collections.Generic.PriorityQueue<TElement, TPriority>
System.Collections.Generic.ReferenceEqualityComparer
System.Diagnostics.CodeAnalysis.AllowNullAttribute
System.Diagnostics.CodeAnalysis.DisallowNullAttribute
System.Diagnostics.CodeAnalysis.DoesNotReturnAttribute
System.Diagnostics.CodeAnalysis.DoesNotReturnIfAttribute
System.Diagnostics.CodeAnalysis.DynamicDependencyAttribute
System.Diagnostics.CodeAnalysis.DynamicallyAccessedMemberTypes
System.Diagnostics.CodeAnalysis.DynamicallyAccessedMembersAttribute
System.Diagnostics.CodeAnalysis.ExperimentalAttribute
System.Diagnostics.CodeAnalysis.MaybeNullAttribute
System.Diagnostics.CodeAnalysis.MaybeNullWhenAttribute
System.Diagnostics.CodeAnalysis.MemberNotNullAttribute
System.Diagnostics.CodeAnalysis.MemberNotNullWhenAttribute
System.Diagnostics.CodeAnalysis.NotNullAttribute
System.Diagnostics.CodeAnalysis.NotNullIfNotNullAttribute
System.Diagnostics.CodeAnalysis.NotNullWhenAttribute
System.Diagnostics.CodeAnalysis.RequiresAssemblyFilesAttribute
System.Diagnostics.CodeAnalysis.RequiresDynamicCodeAttribute
System.Diagnostics.CodeAnalysis.RequiresUnreferencedCodeAttribute
System.Diagnostics.CodeAnalysis.SetsRequiredMembersAttribute
System.Diagnostics.CodeAnalysis.StringSyntaxAttribute
System.Diagnostics.CodeAnalysis.UnconditionalSuppressMessageAttribute
System.Diagnostics.CodeAnalysis.UnscopedRefAttribute
System.Diagnostics.StackTraceHiddenAttribute
System.HashCode
System.Index
System.Net.Http.ReadOnlyMemoryContent
System.Range
System.Runtime.CompilerServices.AsyncMethodBuilderAttribute
System.Runtime.CompilerServices.CallerArgumentExpressionAttribute
System.Runtime.CompilerServices.CollectionBuilderAttribute
System.Runtime.CompilerServices.CompilerFeatureRequiredAttribute
System.Runtime.CompilerServices.DisableRuntimeMarshallingAttribute
System.Runtime.CompilerServices.InterpolatedStringHandlerArgumentAttribute
System.Runtime.CompilerServices.InterpolatedStringHandlerAttribute
System.Runtime.CompilerServices.IsExternalInit
System.Runtime.CompilerServices.ModuleInitializerAttribute
System.Runtime.CompilerServices.OverloadResolutionPriorityAttribute
System.Runtime.CompilerServices.RequiredMemberAttribute
System.Runtime.CompilerServices.SkipLocalsInitAttribute
System.Runtime.CompilerServices.TupleElementNamesAttribute
System.Runtime.InteropServices.SuppressGCTransitionAttribute
System.Runtime.InteropServices.UnmanagedCallersOnlyAttribute
System.Runtime.Versioning.ObsoletedOSPlatformAttribute
System.Runtime.Versioning.RequiresPreviewFeaturesAttribute
System.Runtime.Versioning.SupportedOSPlatformAttribute
System.Runtime.Versioning.SupportedOSPlatformGuardAttribute
System.Runtime.Versioning.TargetPlatformAttribute
System.Runtime.Versioning.UnsupportedOSPlatformAttribute
System.Runtime.Versioning.UnsupportedOSPlatformGuardAttribute
System.Threading.Lock
System.Threading.Tasks.TaskToAsyncResult
System.ValueTuple
System.ValueTuple
System.ValueTuple<T1, T2>
System.ValueTuple<T1, T2, T3>
System.ValueTuple<T1, T2, T3, T4>
System.ValueTuple<T1, T2, T3, T4, T5>
System.ValueTuple<T1, T2, T3, T4, T5, T6>
System.ValueTuple<T1, T2, T3, T4, T5, T6, T7>
System.ValueTuple<T1, T2, T3, T4, T5, T6, T7, TRest> where TRest : struct
System.ITupleInternal

Methods

System.Collections.Concurrent.ConcurrentDictionary<TKey, TValue>.GetOrAdd(TKey key, System.Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument) where TArg : allows ref struct
System.Collections.Generic.CollectionExtensions.AsReadOnly(this System.Collections.Generic.IList list)
System.Collections.Generic.CollectionExtensions.AsReadOnly<TKey, TValue>(this System.Collections.Generic.IDictionary<TKey, TValue> dictionary) where TKey : notnull
System.Collections.Generic.CollectionExtensions.GetValueOrDefault<TKey, TValue>(this System.Collections.Generic.IReadOnlyDictionary<TKey, TValue> dictionary, TKey key)
System.Collections.Generic.CollectionExtensions.GetValueOrDefault<TKey, TValue>(this System.Collections.Generic.IReadOnlyDictionary<TKey, TValue> dictionary, TKey key, TValue defaultValue)
System.Collections.Generic.Dictionary<TKey, TValue>.Remove(TKey key, out TValue value)
System.Collections.Generic.KeyValuePair<TKey, TValue>.Deconstruct(out TKey key, out TValue value)
System.Collections.Generic.Queue.TryDequeue(out T result)
System.Collections.Immutable.ImmutableArray.AsSpan()
System.Collections.Immutable.ImmutableArray.AsSpan(System.Int32 start, System.Int32 length)
System.Collections.Immutable.ImmutableArray.AsSpan(System.Range range)
System.Diagnostics.Process.WaitForExitAsync([System.Threading.CancellationToken cancellationToken = default])
System.IO.Stream.Read(System.Span<System.Byte> buffer)
System.IO.Stream.ReadAsync(System.Memory<System.Byte> buffer, [System.Threading.CancellationToken cancellationToken = default])
System.IO.Stream.ReadAtLeast(System.Span<System.Byte> buffer, System.Int32 minimumBytes, [System.Boolean throwOnEndOfStream = true])
System.IO.Stream.ReadAtLeastAsync(System.Memory<System.Byte> buffer, System.Int32 minimumBytes, [System.Boolean throwOnEndOfStream = true], [System.Threading.CancellationToken cancellationToken = default])
System.IO.Stream.Write(System.ReadOnlySpan<System.Byte> buffer)
System.IO.Stream.WriteAsync(System.ReadOnlyMemory<System.Byte> buffer, [System.Threading.CancellationToken cancellationToken = default])
System.IO.StreamReader.ReadLineAsync()
System.IO.StreamReader.ReadLineAsync(System.Threading.CancellationToken cancellationToken)
System.IO.TextReader.ReadAsync(System.Memory<System.Char> buffer, [System.Threading.CancellationToken cancellationToken = default])
System.IO.TextReader.ReadToEndAsync(System.Threading.CancellationToken cancellationToken)
System.IO.TextWriter.WriteAsync(System.ReadOnlyMemory<System.Char> buffer, [System.Threading.CancellationToken cancellationToken = default])
System.Linq.Enumerable.AggregateBy<TSource, TKey, TAccumulate>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector, System.Func<TKey, TAccumulate> seedSelector, System.Func<TAccumulate, TSource, TAccumulate> func, [System.Collections.Generic.IEqualityComparer? keyComparer = null]) where TKey : notnull
System.Linq.Enumerable.AggregateBy<TSource, TKey, TAccumulate>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector, TAccumulate seed, System.Func<TAccumulate, TSource, TAccumulate> func, [System.Collections.Generic.IEqualityComparer? keyComparer = null]) where TKey : notnull
System.Linq.Enumerable.CountBy<TSource, TKey>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector, [System.Collections.Generic.IEqualityComparer? keyComparer = null]) where TKey : notnull
System.Linq.Enumerable.DistinctBy<TSource, TKey>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector)
System.Linq.Enumerable.DistinctBy<TSource, TKey>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector, System.Collections.Generic.IEqualityComparer? comparer)
System.Linq.Enumerable.Index(this System.Collections.Generic.IEnumerable source)
System.Linq.Enumerable.IntersectBy<TSource, TKey>(this System.Collections.Generic.IEnumerable first, System.Collections.Generic.IEnumerable second, System.Func<TSource, TKey> keySelector)
System.Linq.Enumerable.IntersectBy<TSource, TKey>(this System.Collections.Generic.IEnumerable first, System.Collections.Generic.IEnumerable second, System.Func<TSource, TKey> keySelector, System.Collections.Generic.IEqualityComparer? comparer)
System.Linq.Enumerable.MaxBy<TSource, TKey>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector)
System.Linq.Enumerable.MaxBy<TSource, TKey>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector, System.Collections.Generic.IComparer? comparer)
System.Linq.Enumerable.MinBy<TSource, TKey>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector)
System.Linq.Enumerable.MinBy<TSource, TKey>(this System.Collections.Generic.IEnumerable source, System.Func<TSource, TKey> keySelector, System.Collections.Generic.IComparer? comparer)
System.Linq.Enumerable.OrderDescending(this System.Collections.Generic.IEnumerable source)
System.Linq.Enumerable.OrderDescending(this System.Collections.Generic.IEnumerable source, System.Collections.Generic.IComparer? comparer)
System.Linq.Enumerable.Order(this System.Collections.Generic.IEnumerable source)
System.Linq.Enumerable.Order(this System.Collections.Generic.IEnumerable source, System.Collections.Generic.IComparer? comparer)
System.Linq.Enumerable.ToDictionary<TKey, TValue>(this System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey, TValue>> source) where TKey : notnull
System.Linq.Enumerable.ToDictionary<TKey, TValue>(this System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey, TValue>> source, System.Collections.Generic.IEqualityComparer? comparer) where TKey : notnull
System.Linq.Enumerable.ToHashSet(this System.Collections.Generic.IEnumerable source)
System.Linq.Enumerable.ToHashSet(this System.Collections.Generic.IEnumerable source, System.Collections.Generic.IEqualityComparer? comparer)
System.Linq.Enumerable.UnionBy<TSource, TKey>(this System.Collections.Generic.IEnumerable first, System.Collections.Generic.IEnumerable second, System.Func<TSource, TKey> keySelector)
System.Linq.Enumerable.UnionBy<TSource, TKey>(this System.Collections.Generic.IEnumerable first, System.Collections.Generic.IEnumerable second, System.Func<TSource, TKey> keySelector, System.Collections.Generic.IEqualityComparer? comparer)
System.Linq.Enumerable.Zip<TFirst, TSecond>(this System.Collections.Generic.IEnumerable first, System.Collections.Generic.IEnumerable second)
System.MemoryExtensions.AsSpan(this System.String? text, System.Int32 start, System.Int32 length)
System.MemoryExtensions.CommonPrefixLength(this System.ReadOnlySpan span, System.ReadOnlySpan other)
System.MemoryExtensions.CommonPrefixLength(this System.ReadOnlySpan span, System.ReadOnlySpan other, System.Collections.Generic.IEqualityComparer? comparer)
System.MemoryExtensions.CommonPrefixLength(this System.Span span, System.ReadOnlySpan other)
System.MemoryExtensions.CommonPrefixLength(this System.Span span, System.ReadOnlySpan other, System.Collections.Generic.IEqualityComparer? comparer)
System.MemoryExtensions.ContainsAnyExcept(this System.ReadOnlySpan span, System.ReadOnlySpan values) where T : System.IEquatable?
System.MemoryExtensions.ContainsAnyExcept(this System.ReadOnlySpan span, T value) where T : System.IEquatable?
System.MemoryExtensions.ContainsAnyExcept(this System.ReadOnlySpan span, T value0, T value1) where T : System.IEquatable?
System.MemoryExtensions.ContainsAnyExcept(this System.ReadOnlySpan span, T value0, T value1, T value2) where T : System.IEquatable?
System.MemoryExtensions.ContainsAnyExcept(this System.Span span, System.ReadOnlySpan values) where T : System.IEquatable?
System.MemoryExtensions.ContainsAnyExcept(this System.Span span, T value) where T : System.IEquatable?
System.MemoryExtensions.ContainsAnyExcept(this System.Span span, T value0, T value1) where T : System.IEquatable?
System.MemoryExtensions.ContainsAnyExcept(this System.Span span, T value0, T value1, T value2) where T : System.IEquatable?
System.MemoryExtensions.ContainsAny(this System.Span span, System.ReadOnlySpan values) where T : System.IEquatable?
System.MemoryExtensions.ContainsAny(this System.Span span, T value0, T value1) where T : System.IEquatable?
System.MemoryExtensions.ContainsAny(this System.Span span, T value0, T value1, T value2) where T : System.IEquatable?
System.MemoryExtensions.Contains(this System.ReadOnlySpan span, T value) where T : System.IEquatable?
System.MemoryExtensions.Contains(this System.Span span, T value) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.ReadOnlySpan span, System.ReadOnlySpan values) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.ReadOnlySpan span, T value) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.ReadOnlySpan span, T value0, T value1) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.ReadOnlySpan span, T value0, T value1, T value2) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.Span span, System.ReadOnlySpan values) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.Span span, T value) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.Span span, T value0, T value1) where T : System.IEquatable?
System.MemoryExtensions.IndexOfAnyExcept(this System.Span span, T value0, T value1, T value2) where T : System.IEquatable?
System.Net.Http.HttpContent.CopyTo(System.IO.Stream stream, System.Net.TransportContext? context, System.Threading.CancellationToken cancellationToken)
System.Net.Http.HttpContent.CopyToAsync(System.IO.Stream stream)
System.Net.Http.HttpContent.CopyToAsync(System.IO.Stream stream, System.Net.TransportContext? context)
System.Net.Http.HttpContent.CopyToAsync(System.IO.Stream stream, System.Net.TransportContext? context, System.Threading.CancellationToken cancellationToken)
System.Net.Http.HttpContent.CopyToAsync(System.IO.Stream stream, System.Threading.CancellationToken cancellationToken)
System.Net.Http.HttpContent.ReadAsStream(System.Threading.CancellationToken cancellationToken)
System.Net.Http.HttpContent.ReadAsStream()
System.Net.Http.HttpContent.ReadAsStringAsync(System.Threading.CancellationToken cancellationToken)
System.Net.Sockets.UdpClient.Send(System.ReadOnlySpan<System.Byte> datagram, System.Net.IPEndPoint? endPoint)
System.Net.Sockets.UdpClient.Send(System.ReadOnlySpan<System.Byte> datagram, System.String? hostname, System.Int32 port)
System.Net.Sockets.UdpClient.SendAsync(System.ReadOnlyMemory<System.Byte> datagram, System.Net.IPEndPoint? endPoint, [System.Threading.CancellationToken cancellationToken = default])
System.Net.Sockets.UdpClient.SendAsync(System.ReadOnlyMemory<System.Byte> datagram, System.String? hostname, System.Int32 port, [System.Threading.CancellationToken cancellationToken = default])
System.Net.Sockets.UdpClient.SendAsync(System.ReadOnlyMemory<System.Byte> datagram, [System.Threading.CancellationToken cancellationToken = default])
System.String.Contains(System.Char value)
System.String.Contains(System.Char value, System.StringComparison comparisonType)
System.String.Contains(System.String value, System.StringComparison comparisonType)
System.String.CopyTo(System.Span<System.Char> destination)
System.String.EndsWith(System.Char value)
System.String.GetHashCode(System.StringComparison comparisonType)
System.String.IndexOf(System.Char value, System.StringComparison comparisonType)
System.String.Replace(System.String oldValue, System.String? newValue, System.StringComparison comparisonType)
System.String.ReplaceLineEndings(System.String replacementText)
System.String.ReplaceLineEndings()
System.String.Split(System.Char separator, System.Int32 count, [System.StringSplitOptions options = System.StringSplitOptions.None])
System.String.Split(System.Char separator, [System.StringSplitOptions options = System.StringSplitOptions.None])
System.String.StartsWith(System.Char value)
System.String.TryCopyTo(System.Span<System.Char> destination)
System.Text.Encoding.GetString(System.ReadOnlySpan<System.Byte> bytes)
System.Text.StringBuilder.Append(System.ReadOnlyMemory<System.Char> value)
System.Text.StringBuilder.Append(System.ReadOnlySpan<System.Char> value)
System.Text.StringBuilder.AppendJoin(System.Char separator, params System.Object?[] values)
System.Text.StringBuilder.AppendJoin(System.Char separator, params System.String?[] values)
System.Text.StringBuilder.AppendJoin(System.String? separator, params System.Object?[] values)
System.Text.StringBuilder.AppendJoin(System.String? separator, params System.String?[] values)
System.Text.StringBuilder.AppendJoin(System.Char separator, System.Collections.Generic.IEnumerable values)
System.Text.StringBuilder.AppendJoin(System.String? separator, System.Collections.Generic.IEnumerable values)
System.Text.StringBuilder.Replace(System.ReadOnlySpan<System.Char> oldValue, System.ReadOnlySpan<System.Char> newValue)
System.Text.StringBuilder.Replace(System.ReadOnlySpan<System.Char> oldValue, System.ReadOnlySpan<System.Char> newValue, System.Int32 startIndex, System.Int32 count)
System.Threading.CancellationTokenSource.CancelAsync()
System.Threading.Tasks.Task.WaitAsync(System.Threading.CancellationToken cancellationToken)
System.Threading.Tasks.TaskAsyncEnumerableExtensions.ToBlockingEnumerable(this System.Collections.Generic.IAsyncEnumerable source, [System.Threading.CancellationToken cancellationToken = default])
System.TimeSpan.Multiply(System.Double factor)
System.Type.IsAssignableTo(System.Type? targetType)

Contribution

How to add a new polyfill

Create a new file named .cs in the project Meziantou.Polyfill.Editor
Run Meziantou.Polyfill.Generator

Notes:

All files must be self contained. Use a file class if needed.
If you need to generate a file only when another polyfill is generated, add // when in the file

Changes from Previous Version

No structural changes between v1.0.49 and v1.0.50.

Adoption Assessment

A verified publisher signal is available. Assess fit from the package's supported frameworks, license and dependency graph rather than popularity alone.

Compatibility metadata lists 1 target framework; confirm the exact target used by your application.

Related Guides & Workflows

Learn how to evaluate, integrate, or audit this package in your .NET project.

Audit NuGet dependencies in a .NET project Review NuGet licenses before shipping

Version Stats

23.8K

3.5% of all package downloads

Publisher

meziantou

Packages

Package DLs

Public metadata signal only — not a security, identity or maintenance guarantee.

Details

Authors

meziantou

PublishedSep 9, 2025

Version1.0.50

LicenseMIT

License AuthNot Required

ListedYes

Pre-releaseNo

Links

View on NuGet.org Project Website Download .nupkg License Details Browse Package Contents

Meziantou.Polyfill

Install

Dependencies

Dependency Tree Security Scan

Changelog

README

Meziantou.Polyfill

Installation

Customization

Supported polyfills

Types

Methods

Contribution

How to add a new polyfill

Changes from Previous Version

Adoption Assessment

Related Guides & Workflows