{"id":955,"date":"2023-03-14T15:28:18","date_gmt":"2023-03-14T08:28:18","guid":{"rendered":"https:\/\/csharptutorial.net\/?page_id=955"},"modified":"2023-06-26T14:54:43","modified_gmt":"2023-06-26T07:54:43","slug":"linq-select","status":"publish","type":"page","link":"https:\/\/www.csharptutorial.net\/csharp-linq\/linq-select\/","title":{"rendered":"LINQ Select"},"content":{"rendered":"\n<p><strong>Summary<\/strong>: in this tutorial, you&#8217;ll learn how to use the LINQ <code>Select()<\/code> method to project each element of a sequence into a new form.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Introduction to the LINQ Select method<\/h2>\n\n\n\n<p>The <code>Select()<\/code> method is a LINQ extension method. The <code>Select()<\/code> method projects or transforms each element of a sequence into a new form.<\/p>\n\n\n\n<p>The following shows the syntax of the <code>Select()<\/code> method:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-1\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\">IEnumerable&lt;TResult&gt; Select&lt;TSource, TResult&gt;(\n    <span class=\"hljs-keyword\">this<\/span> IEnumerable&lt;TSource&gt; source, \n    Func&lt;TSource, <span class=\"hljs-keyword\">int<\/span>, TResult&gt; selector\n)<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-1\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>In this syntax:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>TSource<\/code> represents the element&#8217;s type in the <code>source<\/code> sequence.<\/li>\n\n\n\n<li><code>TResult<\/code> is the type of value returned by the <code>selector<\/code>.<\/li>\n\n\n\n<li><code>source<\/code> is an input sequence with the type <a href=\"https:\/\/csharptutorial.net\/csharp-linq\/csharp-ienumerable\/\">IEnumerable&lt;TSource><\/a>.<\/li>\n\n\n\n<li><code>selector<\/code> is a transform function that applies to each element in the <code>source<\/code> sequence. The <code>selector<\/code> has the type <code>Func&lt;TSource, TResult&gt;<\/code>. The second parameter with the type <code>int<\/code> of the transform function is the index of the element in the <code>source<\/code> sequence.<\/li>\n<\/ul>\n\n\n\n<p>The <code>Select()<\/code> method returns an <code>IEnumerable&lt;T&gt;<\/code> whose elements are the result of the transform function on each element of the <code>source<\/code> sequence.<\/p>\n\n\n\n<p>If the <code>source<\/code> or <code>selector<\/code> parameter is null, the <code>Select()<\/code> method throws an <code>ArgumentNullException<\/code>.<\/p>\n\n\n\n<p>Like other LINQ extension methods, the <code>Select()<\/code> method is implemented using deferred execution. It means that the query returned by the <code>Select()<\/code> method is not executed until it is enumerated by a <code><a href=\"https:\/\/csharptutorial.net\/csharp-tutorial\/csharp-foreach\/\">foreach<\/a><\/code> or by calling its <code>GetEnumerator()<\/code> method.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">LINQ Select() method examples<\/h2>\n\n\n\n<p>Let&#8217;s take some examples of using the LINQ <code>Select()<\/code> method.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1) Using the LINQ Select() method to transform a sequence of integer<\/h3>\n\n\n\n<p>The following programs demonstrate how to use the LINQ <code>Select()<\/code> method to create a new sequence of numbers that are squares of the original numbers:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-2\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">static<\/span> System.Console;\n\n\n<span class=\"hljs-keyword\">var<\/span> numbers = <span class=\"hljs-keyword\">new<\/span>&#91;] { <span class=\"hljs-number\">1<\/span>, <span class=\"hljs-number\">5<\/span>, <span class=\"hljs-number\">3<\/span>, <span class=\"hljs-number\">4<\/span>, <span class=\"hljs-number\">7<\/span> };\n\n<span class=\"hljs-keyword\">var<\/span> squares = numbers.Select(n =&gt; n * n);\n\n<span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> square <span class=\"hljs-keyword\">in<\/span> squares)\n{\n    WriteLine(<span class=\"hljs-string\">$\"<span class=\"hljs-subst\">{square}<\/span> \"<\/span>);\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-2\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>How it works.<\/p>\n\n\n\n<p>First, define an array of five numbers:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-3\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">var<\/span> numbers = <span class=\"hljs-keyword\">new<\/span>&#91;] { <span class=\"hljs-number\">1<\/span>, <span class=\"hljs-number\">5<\/span>, <span class=\"hljs-number\">3<\/span>, <span class=\"hljs-number\">4<\/span>, <span class=\"hljs-number\">7<\/span> };<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-3\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Second, create a new sequence of numbers called squares using the <code>Select()<\/code> method.:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-4\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">var<\/span> squares = numbers.Select(n =&gt; n * n);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-4\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>We use the lambda expression <code>n =&gt; n*n<\/code> as the transform function that takes each element of the numbers array, squares it, and returns the resulting square numbers as the element of the new sequence.<\/p>\n\n\n\n<p>Third, write each element of the new sequence to the console using a <code>foreach<\/code> loop and <code>Write()<\/code> method:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-5\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> square <span class=\"hljs-keyword\">in<\/span> squares)\n{\n    Write(<span class=\"hljs-string\">$\"<span class=\"hljs-subst\">{square}<\/span> \"<\/span>);\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-5\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>If you run the program, you&#8217;ll see the following output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-6\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-number\">1<\/span> <span class=\"hljs-number\">25<\/span> <span class=\"hljs-number\">9<\/span> <span class=\"hljs-number\">16<\/span> <span class=\"hljs-number\">49<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-6\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Note that you can chain the <code>Select()<\/code> method with other extensions method like <code><a href=\"https:\/\/csharptutorial.net\/csharp-linq\/linq-orderby\/\">OrderBy()<\/a><\/code>, <code><a href=\"https:\/\/csharptutorial.net\/csharp-linq\/linq-where\/\">Where()<\/a><\/code>, etc. <\/p>\n\n\n\n<p>For example, the following program demonstrates how to chain the <code>Select()<\/code> method with the <code><a href=\"https:\/\/csharptutorial.net\/csharp-linq\/linq-orderby\/\">OrderBy()<\/a><\/code> method to sort the new sequence:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-7\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">static<\/span> System.Console;\n\n\n<span class=\"hljs-keyword\">var<\/span> numbers = <span class=\"hljs-keyword\">new<\/span>&#91;] { <span class=\"hljs-number\">1<\/span>, <span class=\"hljs-number\">5<\/span>, <span class=\"hljs-number\">3<\/span>, <span class=\"hljs-number\">4<\/span>, <span class=\"hljs-number\">7<\/span> };\n\n<span class=\"hljs-keyword\">var<\/span> squares = numbers.Select(n =&gt; n * n)\n                    .OrderBy(n =&gt; n);\n\n\n<span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> square <span class=\"hljs-keyword\">in<\/span> squares)\n{\n    Write(<span class=\"hljs-string\">$\"<span class=\"hljs-subst\">{square}<\/span> \"<\/span>);\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-7\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-8\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-number\">1<\/span> <span class=\"hljs-number\">9<\/span> <span class=\"hljs-number\">16<\/span> <span class=\"hljs-number\">25<\/span> <span class=\"hljs-number\">49<\/span><\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-8\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h3 class=\"wp-block-heading\">2) Using the LINQ Select() method to transform a sequence of strings<\/h3>\n\n\n\n<p>The following program demonstrates how to use <code>Select()<\/code> method to capitalize each string in an array of greetings and write out the modified string to the console:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-9\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">static<\/span> System.Console;\n\n\n<span class=\"hljs-keyword\">var<\/span> greetings = <span class=\"hljs-keyword\">new<\/span> <span class=\"hljs-keyword\">string<\/span>&#91;] { <span class=\"hljs-string\">\"hi\"<\/span>,<span class=\"hljs-string\">\"hello\"<\/span>,<span class=\"hljs-string\">\"hey\"<\/span>, <span class=\"hljs-string\">\"howdy\"<\/span>};\n\n<span class=\"hljs-keyword\">var<\/span> results = greetings.Select(\n    s =&gt; s&#91;<span class=\"hljs-number\">0<\/span>].ToString().ToUpper() + s.Substring(<span class=\"hljs-number\">1<\/span>)\n);\n\n<span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> result <span class=\"hljs-keyword\">in<\/span> results)\n{\n    WriteLine(result);\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-9\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>First, define an array of strings called <code>greetings<\/code> that consists of four strings.<\/p>\n\n\n\n<p>Second, create a new sequence of strings called <code>results<\/code> using the <code>Select()<\/code> method. The lambda <code>expression s => s[0].ToString().ToUpper() + s.Substring(1)<\/code> takes each element of the greetings and capitalizes it.<\/p>\n\n\n\n<p>Third, write each element in the <code>results<\/code> sequence to the console:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-10\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> result <span class=\"hljs-keyword\">in<\/span> results)\n{\n    WriteLine(result);\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-10\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h3 class=\"wp-block-heading\">3) Using the LINQ Select() method to project over a sequence of objects<\/h3>\n\n\n\n<p>The following program illustrates how to use the <code>Select()<\/code> method to get the name of each employee:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-11\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">static<\/span> System.Console;\n\n<span class=\"hljs-keyword\">namespace<\/span> <span class=\"hljs-title\">LINQDemo<\/span>\n{\n    <span class=\"hljs-keyword\">class<\/span> <span class=\"hljs-title\">Employee<\/span>\n    {\n        <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">string<\/span>? Name { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n        <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">string<\/span>? Department { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n        <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">int<\/span> Salary { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n    }\n    <span class=\"hljs-keyword\">class<\/span> <span class=\"hljs-title\">Program<\/span>\n    {\n        <span class=\"hljs-function\"><span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">static<\/span> <span class=\"hljs-keyword\">void<\/span> <span class=\"hljs-title\">Main<\/span>(<span class=\"hljs-params\"><\/span>)<\/span>\n        {\n            <span class=\"hljs-keyword\">var<\/span> employees = <span class=\"hljs-keyword\">new<\/span> List&lt;Employee&gt;() {\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"John\"<\/span>, Department = <span class=\"hljs-string\">\"HR\"<\/span>, Salary = <span class=\"hljs-number\">50000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Jane\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">60000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Bob\"<\/span>, Department = <span class=\"hljs-string\">\"HR\"<\/span>, Salary = <span class=\"hljs-number\">45000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Sara\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">55000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Tom\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">65000<\/span> }\n            };\n\n            <span class=\"hljs-keyword\">var<\/span> names = employees.Select(e =&gt; e.Name);\n\n            <span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> name <span class=\"hljs-keyword\">in<\/span> names)\n            {\n                WriteLine(name);\n            }\n        }\n    }\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-11\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>How it works.<\/p>\n\n\n\n<p>First, define an <code>Employee<\/code> class containing three properties <code>Name<\/code>, <code>Department<\/code>, and <code>Salary<\/code>:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-12\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">class<\/span> <span class=\"hljs-title\">Employee<\/span>\n{\n    <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">string<\/span>? Name { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n    <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">string<\/span>? Department { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n    <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">int<\/span> Salary { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-12\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Second, define a list of employees:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-13\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">var<\/span> employees = <span class=\"hljs-keyword\">new<\/span> List&lt;Employee&gt;() {\n    <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"John\"<\/span>, Department = <span class=\"hljs-string\">\"HR\"<\/span>, Salary = <span class=\"hljs-number\">50000<\/span> },\n    <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Jane\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">60000<\/span> },\n    <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Bob\"<\/span>, Department = <span class=\"hljs-string\">\"HR\"<\/span>, Salary = <span class=\"hljs-number\">45000<\/span> },\n    <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Sara\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">55000<\/span> },\n    <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Tom\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">65000<\/span> }\n};<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-13\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Third, transform a list of <code>Employee<\/code> objects into a list of names using the <code>Select()<\/code> method. The lambda expression <code>e =&gt; e.Name<\/code> returns the full name of each <code>Employee<\/code> object:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-14\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">var<\/span> names = employees.Select(e =&gt; e.Name);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-14\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Finally, write each element of the <code>names<\/code> sequence to the console:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-15\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\"><span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> name <span class=\"hljs-keyword\">in<\/span> names)\n{\n    WriteLine(name);\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-15\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-16\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\">John\nJane\nBob\nSara\nTom<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-16\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Also, you can use the <code>Select()<\/code> method to create a sequence of elements with new a new type. For example:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-17\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\">\n<span class=\"hljs-keyword\">using<\/span> <span class=\"hljs-keyword\">static<\/span> System.Console;\n\n<span class=\"hljs-keyword\">namespace<\/span> <span class=\"hljs-title\">LINQDemo<\/span>\n{\n    <span class=\"hljs-keyword\">class<\/span> <span class=\"hljs-title\">Employee<\/span>\n    {\n        <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">string<\/span>? Name { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n        <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">string<\/span>? Department { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n        <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">int<\/span> Salary { <span class=\"hljs-keyword\">get<\/span>; <span class=\"hljs-keyword\">set<\/span>; }\n    }\n    <span class=\"hljs-keyword\">class<\/span> <span class=\"hljs-title\">Program<\/span>\n    {\n        <span class=\"hljs-function\"><span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">static<\/span> <span class=\"hljs-keyword\">void<\/span> <span class=\"hljs-title\">Main<\/span>(<span class=\"hljs-params\"><\/span>)<\/span>\n        {\n            <span class=\"hljs-keyword\">var<\/span> employees = <span class=\"hljs-keyword\">new<\/span> List&lt;Employee&gt;() {\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"John\"<\/span>, Department = <span class=\"hljs-string\">\"HR\"<\/span>, Salary = <span class=\"hljs-number\">50000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Jane\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">60000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Bob\"<\/span>, Department = <span class=\"hljs-string\">\"HR\"<\/span>, Salary = <span class=\"hljs-number\">45000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Sara\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">55000<\/span> },\n                <span class=\"hljs-keyword\">new<\/span> Employee { Name = <span class=\"hljs-string\">\"Tom\"<\/span>, Department = <span class=\"hljs-string\">\"IT\"<\/span>, Salary = <span class=\"hljs-number\">65000<\/span> }\n            };\n\n            <span class=\"hljs-keyword\">var<\/span> payroll = employees.Select(e =&gt; <span class=\"hljs-keyword\">new<\/span> {\n                e.Name,\n                e.Salary\n            });\n\n            <span class=\"hljs-keyword\">foreach<\/span> (<span class=\"hljs-keyword\">var<\/span> employee <span class=\"hljs-keyword\">in<\/span> payroll)\n            {\n                WriteLine(employee);\n            }\n        }\n    }\n}\n<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-17\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-18\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\">{ Name = John, Salary = <span class=\"hljs-number\">50000<\/span> }\n{ Name = Jane, Salary = <span class=\"hljs-number\">60000<\/span> }\n{ Name = Bob, Salary = <span class=\"hljs-number\">45000<\/span> }\n{ Name = Sara, Salary = <span class=\"hljs-number\">55000<\/span> }\n{ Name = Tom, Salary = <span class=\"hljs-number\">65000<\/span> }<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-18\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>In this example, the lambda expression returns an object with a new <a href=\"https:\/\/csharptutorial.net\/csharp-tutorial\/csharp-anonymous-type\/\">anonymous type<\/a> with two properties <code>Name<\/code> and <code>Salary<\/code>:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-19\" data-shcb-language-name=\"C#\" data-shcb-language-slug=\"cs\"><span><code class=\"hljs language-cs\">e =&gt; <span class=\"hljs-keyword\">new<\/span> {\n    e.Name,\n    e.Salary\n}<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-19\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">C#<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">cs<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\">Summary<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Use the LINQ <code>Select()<\/code> method to project each element of a sequence into a new form.<\/li>\n<\/ul>\n<div class=\"helpful-block-content\" data-title=\"\">\n\t<header>\n\t\t<div class=\"wth-question\">Was this tutorial helpful ?<\/div>\n\t\t<div class=\"wth-thumbs\">\n\t\t\t<button\n\t\t\t\tdata-post=\"955\"\n\t\t\t\tdata-post-url=\"https:\/\/www.csharptutorial.net\/csharp-linq\/linq-select\/\"\n\t\t\t\tdata-post-title=\"LINQ Select\"\n\t\t\t\tdata-response=\"1\"\n\t\t\t\tclass=\"wth-btn-rounded wth-yes-btn\"\n\t\t\t>\n\t\t\t\t<svg\n\t\t\t\t\txmlns=\"http:\/\/www.w3.org\/2000\/svg\"\n\t\t\t\t\tviewBox=\"0 0 24 24\"\n\t\t\t\t\tfill=\"none\"\n\t\t\t\t\tstroke=\"currentColor\"\n\t\t\t\t\tstroke-width=\"2\"\n\t\t\t\t\tstroke-linecap=\"round\"\n\t\t\t\t\tstroke-linejoin=\"round\"\n\t\t\t\t\tclass=\"feather feather-thumbs-up block w-full h-full\"\n\t\t\t\t>\n\t\t\t\t\t<path\n\t\t\t\t\t\td=\"M14 9V5a3 3 0 0 0-3-3l-4 9v11h11.28a2 2 0 0 0 2-1.7l1.38-9a2 2 0 0 0-2-2.3zM7 22H4a2 2 0 0 1-2-2v-7a2 2 0 0 1 2-2h3\"\n\t\t\t\t\t><\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t<span class=\"sr-only\"> Yes <\/span>\n\t\t\t<\/button>\n\n\t\t\t<button\n\t\t\t\tdata-response=\"0\"\n\t\t\t\tdata-post=\"955\"\n\t\t\t\tdata-post-url=\"https:\/\/www.csharptutorial.net\/csharp-linq\/linq-select\/\"\n\t\t\t\tdata-post-title=\"LINQ Select\"\n\t\t\t\tclass=\"wth-btn-rounded wth-no-btn\"\n\t\t\t>\n\t\t\t\t<svg\n\t\t\t\t\txmlns=\"http:\/\/www.w3.org\/2000\/svg\"\n\t\t\t\t\tviewBox=\"0 0 24 24\"\n\t\t\t\t\tfill=\"none\"\n\t\t\t\t\tstroke=\"currentColor\"\n\t\t\t\t\tstroke-width=\"2\"\n\t\t\t\t\tstroke-linecap=\"round\"\n\t\t\t\t\tstroke-linejoin=\"round\"\n\t\t\t\t>\n\t\t\t\t\t<path\n\t\t\t\t\t\td=\"M10 15v4a3 3 0 0 0 3 3l4-9V2H5.72a2 2 0 0 0-2 1.7l-1.38 9a2 2 0 0 0 2 2.3zm7-13h2.67A2.31 2.31 0 0 1 22 4v7a2.31 2.31 0 0 1-2.33 2H17\"\n\t\t\t\t\t><\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t<span class=\"sr-only\"> No <\/span>\n\t\t\t<\/button>\n\t\t<\/div>\n\t<\/header>\n\n\t<div class=\"wth-form hidden\">\n\t\t<div class=\"wth-form-wrapper\">\n\t\t\t<div class=\"wth-title\"><\/div>\n\t\t\t\n\t\t\t<textarea class=\"wth-message\"><\/textarea>\n\n\t\t\t<button class=\"btn btn-primary wth-btn-submit\">Send<\/button>\n\t\t\t<button class=\"btn wth-btn-cancel\">Cancel<\/button>\n\t\t\n\t\t<\/div>\n\t<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>In this tutorial, you&#8217;ll learn how to use the LINQ Select() method to project each element of a sequence into a new form.<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":919,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-955","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/pages\/955","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/comments?post=955"}],"version-history":[{"count":5,"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/pages\/955\/revisions"}],"predecessor-version":[{"id":2454,"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/pages\/955\/revisions\/2454"}],"up":[{"embeddable":true,"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/pages\/919"}],"wp:attachment":[{"href":"https:\/\/www.csharptutorial.net\/wp-json\/wp\/v2\/media?parent=955"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}