MapsterMapper/Mapster

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A fast, fun and stimulating object to object Mapper

Stars: 5.2k
Forks: 410
Open beginner issues: 0
Indexed issues: 73
Avg merge: 2d 12h
Merged PRs (30d): 6

Dominant language: C#
License: MIT
Last GitHub push: Jun 12, 2026
Latest indexed: Sep 19, 2026
Contributing guide: Contributing guide
Code of conduct: No code of conduct
Beginner labels: help wanted good first issue

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73 open issues indexed

Please use Discussions for Q&A Open

MapsterMapper/Mapster#234 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Tool generates empty mapper Open

bug waiting for info

MapsterMapper/Mapster#339 · 15 comments · 5 reactions · 0 assignees · Indexed Sep 19, 2026
DateTimeOffset to DateTime throws Mapster.CompileException Open

improvement

MapsterMapper/Mapster#356 · 7 comments · 2 reactions · 1 assignee · Indexed Sep 19, 2026
Feat: more powerful Attribute-based configuration Open

config features feature request

MapsterMapper/Mapster#360 · 0 comments · 2 reactions · 0 assignees · Indexed Sep 19, 2026
mapster tool generates non-public interface method/property implementation Open

bug help wanted

MapsterMapper/Mapster#399 · 10 comments · 0 reactions · 1 assignee · Indexed Sep 19, 2026
Properties do not map properly Open

bug waiting for info

MapsterMapper/Mapster#407 · 11 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Generated Mapster.Tool mappers fails Dependency Injection Open

bug

MapsterMapper/Mapster#424 · 4 comments · 1 reaction · 1 assignee · Indexed Sep 19, 2026
[Tool][Feature request] Copy XmlDoc for generated classes Open

MapsterMapper/Mapster#428 · 2 comments · 1 reaction · 0 assignees · Indexed Sep 19, 2026
Why is the list collection mapping configuration invalid Open

improvement

MapsterMapper/Mapster#439 · 1 comment · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Will you be adding an AssertConfigurationIsValid() equivalent? Open

feature request

MapsterMapper/Mapster#446 · 6 comments · 10 reactions · 0 assignees · Indexed Sep 19, 2026
[Feature Request] add api to get differents properties(or fields) when map to exists dst? Open

feature request

MapsterMapper/Mapster#477 · 1 comment · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Support XML documentation comments? Open

good first issue help wanted improvement open for PR

MapsterMapper/Mapster#492 · 7 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Mapster.JsonNet does not support Enum to string mapping Open

bug

MapsterMapper/Mapster#502 · 0 comments · 0 reactions · 1 assignee · Indexed Sep 19, 2026
Ignore nullable property does warning CS8603 Open

improvement waiting for info

MapsterMapper/Mapster#520 · 8 comments · 2 reactions · 0 assignees · Indexed Sep 19, 2026
Pass additional configuration settings to Mapster.Tool Open

feature request

MapsterMapper/Mapster#528 · 0 comments · 1 reaction · 0 assignees · Indexed Sep 19, 2026
Please support arbitrary parameters on interface when generating mapper Open

feature request

MapsterMapper/Mapster#529 · 2 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Attribute based CodeGeneration RequireDestinationMemberSource propagate to dependents Open

bug

MapsterMapper/Mapster#541 · 1 comment · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Is there going to be a [MaxDepth] attribute? Open

good first issue improvement open for PR

MapsterMapper/Mapster#550 · 1 comment · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Feature request: also force all source properties to be in destination Open

improvement open for PR

MapsterMapper/Mapster#551 · 1 comment · 2 reactions · 0 assignees · Indexed Sep 19, 2026
Mapster.TypeAdapterConfig Open

waiting for info

MapsterMapper/Mapster#556 · 2 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Mapster.Tool interface mapping should use inheritdoc Open

feature request good first issue help wanted open for PR

MapsterMapper/Mapster#565 · 2 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Error: stack overflow when RequireExplicitMapping = true Open

bug configuration problem

MapsterMapper/Mapster#571 · 5 comments · 1 reaction · 0 assignees · Indexed Sep 19, 2026
Provide more details on null reference questions Open

improvement

MapsterMapper/Mapster#609 · 4 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Adapt to array does not work Open

bug

MapsterMapper/Mapster#610 · 4 comments · 0 reactions · 1 assignee · Indexed Sep 19, 2026
Source Generators with IMapper Interface Open

feature request

MapsterMapper/Mapster#622 · 12 comments · 3 reactions · 0 assignees · Indexed Sep 19, 2026
dotnet mapper ... -p generates code that can't be compiled. Open

bug

MapsterMapper/Mapster#665 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Compile doesn't throw exceptions while configuring with attributes Open

bug configuration problem

MapsterMapper/Mapster#666 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Generic IEnumerator not disposed Open

improvement

MapsterMapper/Mapster#667 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Can't use conditional mapping with different types of source field Open

help wanted improvement

MapsterMapper/Mapster#673 · 3 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
mapster is missing NuGet package README file Open

improvement

MapsterMapper/Mapster#675 · 1 comment · 0 reactions · 0 assignees · Indexed Sep 19, 2026
How can I obtain the changed field values after mapping two entities? Open

feature request

MapsterMapper/Mapster#692 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Mapping must be called using ServiceAdapter Open

bug

MapsterMapper/Mapster#704 · 3 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Separate namespaces to avoid ambiguous references Open

improvement

MapsterMapper/Mapster#705 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Misleading exception message for ctor argument names Open

bug configuration problem

MapsterMapper/Mapster#719 · 6 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Inspecting property maps for validation and copying of metadata Open

feature request ProjectToType features

MapsterMapper/Mapster#721 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Unable to map classes with generics Open

configuration problem

MapsterMapper/Mapster#724 · 1 comment · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Inheritance and scanning assembly for IRegister. Open

improvement

MapsterMapper/Mapster#726 · 5 comments · 2 reactions · 0 assignees · Indexed Sep 19, 2026
Hi, does Mapster cache class information? Is there a possibility of memory leakage when reloading classes using ALC Open

MapsterMapper/Mapster#727 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Map<TSource, TDestination> should have class constraint for TDestination Open

configuration problem

MapsterMapper/Mapster#736 · 0 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
When using TypeAdapterConfig.GlobalSettings.Default.IgnoreNullValues(true), it causes the Mapper function to be called twice. Open

waiting for info

MapsterMapper/Mapster#737 · 5 comments · 0 reactions · 1 assignee · Indexed Sep 19, 2026
Tweaking null propagation easily Open

help wanted improvement

MapsterMapper/Mapster#740 · 3 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
wish to add the ability to ignore a copy of a property when it has a specific value. For example, null, empty string, empty collection Open

Ignore features improvement waiting for info

MapsterMapper/Mapster#747 · 2 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
BuildAdapter().AdaptToType<T>() does not include all expected properties when source is using inheritance Open

bug configuration problem waiting for info

MapsterMapper/Mapster#776 · 6 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Polymorphic mapping with collections maps only base class properties Open

bug configuration problem

MapsterMapper/Mapster#793 · 11 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
[Enhancement][CI] Add Branch Protection, Code Analysis and Project board Open

improvement

MapsterMapper/Mapster#831 · 20 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Adapt(source, destination) does not work when destination is a C# record Open

improvement need Docs modify

MapsterMapper/Mapster#832 · 45 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Add an overload to the Adapt method to allow using a local, temporary configuration. Open

config features feature request

MapsterMapper/Mapster#833 · 5 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
Unification build Properties Open

build improvement

MapsterMapper/Mapster#843 · 0 comments · 1 reaction · 0 assignees · Indexed Sep 19, 2026
[Docs][CI] Ensure docfx links stay valid, prepare future xml API docs options, keep docs simple maintainable and introduce CI integration for this Open

docs improvement

MapsterMapper/Mapster#846 · 6 comments · 0 reactions · 0 assignees · Indexed Sep 19, 2026
[Tests] Local Testing of single Mapster Projects fails for SolutionDir is not always set when building a project directly via dotnet test Open

improvement

MapsterMapper/Mapster#848 · 10 comments · 0 reactions · 1 assignee · Indexed Sep 19, 2026

MapsterMapper/Mapster

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