{"componentChunkName":"component---src-pages-markdown-remark-fields-slug-js","path":"/engineering/csharp-init-only-setters-property/","result":{"data":{"markdownRemark":{"id":"a9c5ebcf-965a-556b-9b54-d40934fe1b07","excerpt":"Introduction In C# 9.0, there are multiple features introduced. One of them is the Init-Only setters property feature. To use this feature, there are two pre…","html":"<h2 id=\"introduction\" style=\"position:relative;\"><a href=\"#introduction\" aria-label=\"introduction permalink\" class=\"anchor before\"><svg aria-hidden=\"true\" focusable=\"false\" height=\"16\" version=\"1.1\" viewBox=\"0 0 16 16\" width=\"16\"><path fill-rule=\"evenodd\" d=\"M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z\"></path></svg></a>Introduction</h2>\n<p>In C# 9.0, there are multiple features introduced. One of them is the <strong>Init-Only setters property</strong> feature. To use this feature, there are two pre-requisite.</p>\n<ol>\n<li>You should have the .NET 5 SDK installed in your system. If not, you can download and install it from <a href=\"https://dotnet.microsoft.com/download/dotnet/5.0\">here</a>.</li>\n<li>You should have at least a 16.7 version or the latest version of Visual Studio 2019. If not, then you have to update your Visual Studio 2019 to the latest version.</li>\n</ol>\n<p>After this setup, you are ready to go with the Init-Only setters property feature.</p>\n<p>Before knowing more about this feature, first, we will understand how we are using properties currently in C#.</p>\n<h2 id=\"how-we-are-using-the-properties-currently\" style=\"position:relative;\"><a href=\"#how-we-are-using-the-properties-currently\" aria-label=\"how we are using the properties currently permalink\" class=\"anchor before\"><svg aria-hidden=\"true\" focusable=\"false\" height=\"16\" version=\"1.1\" viewBox=\"0 0 16 16\" width=\"16\"><path fill-rule=\"evenodd\" d=\"M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z\"></path></svg></a>How we are using the properties currently</h2>\n<pre class=\"grvsc-container dark-default-dark\" data-language=\"c#\" data-index=\"0\"><code class=\"grvsc-code\"><span class=\"grvsc-line\"><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk12\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> { </span><span class=\"mtk12\">get</span><span class=\"mtk1\">; </span><span class=\"mtk12\">set</span><span class=\"mtk1\">; }</span></span></code></pre>\n<p>This is the way how we are using the properties, but whenever if we don't want to change the value of a property outside of a class and make them readable publicly, then we generally define the property as below.</p>\n<pre class=\"grvsc-container dark-default-dark\" data-language=\"c#\" data-index=\"1\"><code class=\"grvsc-code\"><span class=\"grvsc-line\"><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk12\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> { </span><span class=\"mtk12\">get</span><span class=\"mtk1\">; </span><span class=\"mtk10\">private</span><span class=\"mtk1\"> </span><span class=\"mtk12\">set</span><span class=\"mtk1\">; }</span></span></code></pre>\n<p>In that case, the Id property can not be set outside of the class, and to set this property, we have to introduce a constructor or a public method that can set the value of the Id field. Like below</p>\n<pre class=\"grvsc-container dark-default-dark\" data-language=\"c#\" data-index=\"2\"><code class=\"grvsc-code\"><span class=\"grvsc-line\"><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">class</span><span class=\"mtk1\"> </span><span class=\"mtk10\">Company</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">{</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> { </span><span class=\"mtk4\">get</span><span class=\"mtk1\">; </span><span class=\"mtk4\">private</span><span class=\"mtk1\"> </span><span class=\"mtk4\">set</span><span class=\"mtk1\">; }</span></span>\n<span class=\"grvsc-line\"></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk11\">Company</span><span class=\"mtk1\">(</span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">id</span><span class=\"mtk1\">) </span><span class=\"mtk3\">// Constructor</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    {</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">        </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> = </span><span class=\"mtk12\">id</span><span class=\"mtk1\">;</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    }</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">void</span><span class=\"mtk1\"> </span><span class=\"mtk11\">SetId</span><span class=\"mtk1\">(</span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">id</span><span class=\"mtk1\">) </span><span class=\"mtk3\">//Public method</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    {</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">        </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> = </span><span class=\"mtk12\">id</span><span class=\"mtk1\">;</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    }</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">}</span></span></code></pre>\n<p>Below are the problems which arise by using the above method</p>\n<ol>\n<li>We are not able to set the property value by using the <em>object initialization</em></li>\n<li>If we want to set the property as <em>immutable</em> (Value can not be changed), then we can not achieve this because any public method can change the value of that property, so here the property is <em>mutable</em> (Value can be changed).</li>\n</ol>\n<p>To fix those issues, In C# 9.0 Init-Only setters property feature was introduced. Have a look at this.</p>\n<h2 id=\"init-only-setters-property\" style=\"position:relative;\"><a href=\"#init-only-setters-property\" aria-label=\"init only setters property permalink\" class=\"anchor before\"><svg aria-hidden=\"true\" focusable=\"false\" height=\"16\" version=\"1.1\" viewBox=\"0 0 16 16\" width=\"16\"><path fill-rule=\"evenodd\" d=\"M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z\"></path></svg></a>Init-Only Setters Property</h2>\n<p>Init-Only setters property gives us the flexibility to set the value of a property by using the object initializer as well the property is also immutable. So that will resolve the above issues, which were with the <em>private set</em> property.</p>\n<pre class=\"grvsc-container dark-default-dark\" data-language=\"c#\" data-index=\"3\"><code class=\"grvsc-code\"><span class=\"grvsc-line\"><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">class</span><span class=\"mtk1\"> </span><span class=\"mtk10\">Company</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">{</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> { </span><span class=\"mtk4\">get</span><span class=\"mtk1\">; init; }</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">}</span></span></code></pre>\n<pre class=\"grvsc-container dark-default-dark\" data-language=\"c#\" data-index=\"4\"><code class=\"grvsc-code\"><span class=\"grvsc-line\"><span class=\"mtk10\">Company</span><span class=\"mtk1\"> </span><span class=\"mtk12\">comp</span><span class=\"mtk1\">=</span><span class=\"mtk4\">new</span><span class=\"mtk1\"> </span><span class=\"mtk10\">Company</span><span class=\"mtk1\">{</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk12\">Id</span><span class=\"mtk1\">=</span><span class=\"mtk7\">1</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">}; </span><span class=\"mtk3\">// It works fine if we initialize here</span></span></code></pre>\n<p>As we can, it is perfectly fine to set the value during object initialization.</p>\n<pre class=\"grvsc-container dark-default-dark\" data-language=\"c#\" data-index=\"5\"><code class=\"grvsc-code\"><span class=\"grvsc-line\"><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">class</span><span class=\"mtk1\"> </span><span class=\"mtk10\">Company</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">{</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> { </span><span class=\"mtk4\">get</span><span class=\"mtk1\">; init; }</span></span>\n<span class=\"grvsc-line\"></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">     </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk11\">Company</span><span class=\"mtk1\">(</span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">id</span><span class=\"mtk1\">)</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    {</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">        </span><span class=\"mtk4\">this</span><span class=\"mtk1\">.</span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> = </span><span class=\"mtk12\">Id</span><span class=\"mtk1\">;</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    }</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">}</span></span></code></pre>\n<p>We can define the constructor as well to initialize the Init-Only setters property. </p>\n<p>If we will try to create a method in the class and want to change the value Init-Only setters property, then it will give us the compile-time error.</p>\n<pre class=\"grvsc-container dark-default-dark\" data-language=\"c#\" data-index=\"6\"><code class=\"grvsc-code\"><span class=\"grvsc-line\"><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">class</span><span class=\"mtk1\"> </span><span class=\"mtk10\">Company</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">{</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> { </span><span class=\"mtk4\">get</span><span class=\"mtk1\">; init; }</span></span>\n<span class=\"grvsc-line\"></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    </span><span class=\"mtk4\">public</span><span class=\"mtk1\"> </span><span class=\"mtk4\">void</span><span class=\"mtk1\"> </span><span class=\"mtk11\">SetId</span><span class=\"mtk1\">(</span><span class=\"mtk4\">int</span><span class=\"mtk1\"> </span><span class=\"mtk12\">Id</span><span class=\"mtk1\">)</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    {</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">        </span><span class=\"mtk4\">this</span><span class=\"mtk1\">.</span><span class=\"mtk12\">Id</span><span class=\"mtk1\"> = </span><span class=\"mtk12\">Id</span><span class=\"mtk1\">; </span><span class=\"mtk3\">// Compile-time Error</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">    }</span></span>\n<span class=\"grvsc-line\"><span class=\"mtk1\">}</span></span></code></pre>\n<h2 id=\"conclusion\" style=\"position:relative;\"><a href=\"#conclusion\" aria-label=\"conclusion permalink\" class=\"anchor before\"><svg aria-hidden=\"true\" focusable=\"false\" height=\"16\" version=\"1.1\" viewBox=\"0 0 16 16\" width=\"16\"><path fill-rule=\"evenodd\" d=\"M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z\"></path></svg></a>Conclusion</h2>\n<p>In this article, we learned how we are setting the properties in C# currently and the new C# 9.0 feature Init-Only Setters Property. Also, we understood how this feature helps us to set the property value with the object initialization.</p>\n<style class=\"grvsc-styles\">\n  .grvsc-container {\n    overflow: auto;\n    -webkit-overflow-scrolling: touch;\n    padding-top: 1rem;\n    padding-top: var(--grvsc-padding-top, var(--grvsc-padding-v, 1rem));\n    padding-bottom: 1rem;\n    padding-bottom: var(--grvsc-padding-bottom, var(--grvsc-padding-v, 1rem));\n    border-radius: 8px;\n    border-radius: var(--grvsc-border-radius, 8px);\n    font-feature-settings: normal;\n  }\n  \n  .grvsc-code {\n    display: inline-block;\n    min-width: 100%;\n  }\n  \n  .grvsc-line {\n    display: inline-block;\n    box-sizing: border-box;\n    width: 100%;\n    padding-left: 1.5rem;\n    padding-left: var(--grvsc-padding-left, var(--grvsc-padding-h, 1.5rem));\n    padding-right: 1.5rem;\n    padding-right: var(--grvsc-padding-right, var(--grvsc-padding-h, 1.5rem));\n  }\n  \n  .grvsc-line-highlighted {\n    background-color: var(--grvsc-line-highlighted-background-color, transparent);\n    box-shadow: inset var(--grvsc-line-highlighted-border-width, 4px) 0 0 0 var(--grvsc-line-highlighted-border-color, transparent);\n  }\n  \n  .dark-default-dark {\n    background-color: #1E1E1E;\n    color: #D4D4D4;\n  }\n  .dark-default-dark .mtk4 { color: #569CD6; }\n  .dark-default-dark .mtk1 { color: #D4D4D4; }\n  .dark-default-dark .mtk12 { color: #9CDCFE; }\n  .dark-default-dark .mtk10 { color: #4EC9B0; }\n  .dark-default-dark .mtk11 { color: #DCDCAA; }\n  .dark-default-dark .mtk3 { color: #6A9955; }\n  .dark-default-dark .mtk7 { color: #B5CEA8; }\n</style>","headings":[{"value":"Introduction","depth":2},{"value":"How we are using the properties currently","depth":2},{"value":"Init-Only Setters Property","depth":2},{"value":"Conclusion","depth":2}],"fields":{"slug":"/engineering/csharp-init-only-setters-property/"},"frontmatter":{"metatitle":null,"metadescription":null,"description":"In this article, we will talk about Init-Only Setters Property in C#.","title":"C# Init-Only Setters Property","canonical":null,"date":"July 15, 2021","updated_date":null,"tags":["C#","Properties","Init"],"coverImage":{"childImageSharp":{"fluid":{"aspectRatio":1.5037593984962405,"src":"/static/e2d2c98e4cd2dbf38d3e2ddeaba94705/03979/coverimage.png","srcSet":"/static/e2d2c98e4cd2dbf38d3e2ddeaba94705/f5f11/coverimage.png 200w,\n/static/e2d2c98e4cd2dbf38d3e2ddeaba94705/6d133/coverimage.png 400w,\n/static/e2d2c98e4cd2dbf38d3e2ddeaba94705/03979/coverimage.png 800w,\n/static/e2d2c98e4cd2dbf38d3e2ddeaba94705/aca38/coverimage.png 1200w","sizes":"(max-width: 800px) 100vw, 800px"}}},"author":{"id":"Hemant Manwani","github":"hemant404","bio":"Hemant Manwani is a Software Engineer at LoginRadius who is interested in how the web works and developer tools that make working with web easier.","avatar":null}}}},"pageContext":{"id":"a9c5ebcf-965a-556b-9b54-d40934fe1b07","fields__slug":"/engineering/csharp-init-only-setters-property/","__params":{"fields__slug":"engineering"}}},"staticQueryHashes":["1171199041","1384082988","1711371485","1753898100","2100481360","229320306","23180105","528864852"]}