--- title: C# Tip: Use required members to prevent invalid object... description: Explains how the C# required keyword forces properties to be set during object initialization, preventing half-configured objects, using a BoardGame example.... canonical: https://daily.dev/posts/c-tip-use-required-members-to-prevent-invalid-object-initialization-beware-of-setsrequiredmembers-amt869os4 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: C# Tip: Use required members to prevent invalid object initialization (beware of SetsRequiredMembers attribute!) | daily.dev og:description: Explains how the C# required keyword forces properties to be set during object initialization, preventing half-configured objects, using a BoardGame example.... og:url: https://daily.dev/posts/c-tip-use-required-members-to-prevent-invalid-object-initialization-beware-of-setsrequiredmembers-amt869os4 og:image: https://api.daily.dev/og/posts/AMT869Os4.png og:image:alt: C# Tip: Use required members to prevent invalid object initialization (beware of SetsRequiredMembers attribute!) og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # C# Tip: Use required members to prevent invalid object initialization (beware of SetsRequiredMembers attribute!) **[Code4IT](https://daily.dev/sources/code4it)** · 6 min read · 0 upvotes · 0 comments ## Summary Explains how the C# required keyword forces properties to be set during object initialization, preventing half-configured objects, using a BoardGame example. Compares required members with constructor-based validation and discusses when to use each. Warns that the SetsRequiredMembers attribute, used to tell the compiler a constructor initializes all required members, can be misused: if the constructor forgets to set a required property, the compiler stays silent, allowing invalid objects to be created. Includes a checklist for deciding when to adopt required members. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What does the SetsRequiredMembers attribute do in C# and why is it risky? SetsRequiredMembers tells the compiler that a constructor initializes all of a class's required members, so object creation through that constructor is allowed without the usual compile-time check. The risk is that if the constructor actually forgets to set one of the required properties, the compiler does not catch it, letting a half-initialized object slip through silently. _daily.dev surfaces practical C# patterns like this for developers tightening up object initialization safety._ ### How is the required keyword in C# different from using a constructor to enforce mandatory properties? The required keyword marks individual properties as mandatory independently of each other, forcing them to be set via object initializer syntax or a constructor, while a constructor enforces all its parameters together with any validation logic running immediately. Constructors suit domain invariants that must hold together, such as a DateRange where StartDate must precede EndDate; required suits independent mandatory fields like Name and MinPlayers on a BoardGame. _developers choosing between initialization patterns for domain models can compare approaches on daily.dev._ ## Similar posts on daily.dev - [Adding Properties with extension methods in C\# 14](https://daily.dev/posts/adding-properties-with-extension-methods-in-c-14-aaqhtts73) · We Are .NET · 1 upvotes · 0 comments - [Extension Properties: C\# 14’s Game-Changer for Cleaner Code](https://daily.dev/posts/extension-properties-c-14-s-game-changer-for-cleaner-code-aawdgf4pc) · Telerik · 0 upvotes · 0 comments - [C\# Extension Members](https://daily.dev/posts/c-extension-members-1anekbztp) · JetBrains · 18 upvotes · 1 comments --- Tags: [#.net](https://daily.dev/tags/.net), [#c#](https://daily.dev/tags/c#) [View this post on daily.dev](https://daily.dev/posts/c-tip-use-required-members-to-prevent-invalid-object-initialization-beware-of-setsrequiredmembers-amt869os4) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"C# Tip: Use required members to prevent invalid object initialization (beware of SetsRequiredMembers attribute!)","url":"https://daily.dev/posts/c-tip-use-required-members-to-prevent-invalid-object-initialization-beware-of-setsrequiredmembers-amt869os4","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/c-tip-use-required-members-to-prevent-invalid-object-initialization-beware-of-setsrequiredmembers-amt869os4"},"datePublished":"2026-10-04T13:07:21.658Z","dateModified":"2026-10-04T13:18:51.650Z","description":"Explains how the C# required keyword forces properties to be set during object initialization, preventing half-configured objects, using a BoardGame example....","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2b4ae09af245a199c62af225aa4a0333?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2b4ae09af245a199c62af225aa4a0333?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Code4IT","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Code4IT","logo":"https://media.daily.dev/image/upload/s--OaaG4G10--/f_auto,q_auto/v1791119049/logos/code4it?_a=BAMAMicg0","url":"https://daily.dev/sources/code4it"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/c-tip-use-required-members-to-prevent-invalid-object-initialization-beware-of-setsrequiredmembers-amt869os4","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":".net,c#","timeRequired":"PT6M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Code4IT","item":"https://daily.dev/sources/code4it"},{"@type":"ListItem","position":3,"name":"C# Tip: Use required members to prevent invalid object initialization (beware of SetsRequiredMembers attribute!)"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/c-tip-use-required-members-to-prevent-invalid-object-initialization-beware-of-setsrequiredmembers-amt869os4#faq","mainEntity":[{"@type":"Question","name":"What does the SetsRequiredMembers attribute do in C# and why is it risky?","acceptedAnswer":{"@type":"Answer","text":"SetsRequiredMembers tells the compiler that a constructor initializes all of a class's required members, so object creation through that constructor is allowed without the usual compile-time check. 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