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POInitializing a Generic.List in C#
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copied!<p>In C#, I can initialize a list using the following syntax.</p> <pre><code>List<int> intList= new List<int>() { 1, 2, 3 }; </code></pre> <p>I would like to know how that <code>{}</code> syntax works, and if it has a name. There is a constructor that takes an <code>IEnumerable</code>, you could call that.</p> <pre><code>List<int> intList= new List<int>(new int[]{ 1, 2, 3 }); </code></pre> <p>That seems more "standard". When I deconstruct the default constructor for the List I only see </p> <pre><code>this._items = Array.Empty; </code></pre> <p>I would like to be able to do this.</p> <pre><code>CustomClass abc = new CustomClass() {1, 2, 3}; </code></pre> <p>And be able to use the <code>1, 2, 3</code> list. How does this work?</p> <p><strong>Update</strong> </p> <p>Jon Skeet answered</p> <blockquote> <p>It's calling the parameterless constructor, and then calling Add:</p> </blockquote> <pre><code>> List<int> tmp = new List<int>(); > tmp.Add(1); tmp.Add(2); tmp.Add(3); > List<int> intList = tmp; </code></pre> <p>I understand what is does. I want to know how. How does that syntax know to call the Add method? </p> <p><strong>Update</strong></p> <p>I know, how cliche to accept a Jon Skeet answer. But, the example with the strings and ints is awesome. Also a very helpful MSDN page is:</p> <ul> <li><em><a href="http://msdn.microsoft.com/en-us/library/bb384062.aspx" rel="noreferrer">Object and Collection Initializers (C# Programming Guide)</a></em></li> </ul>

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