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copied!<p>Use a lambda expression</p> <pre><code>MyClass result = list.Find(x => x.GetId() == "xy"); </code></pre> <hr> <p>Note: C# has a built-in syntax for properties. Instead of writing Set- and Get-methods (how you could be used to it from Java), write</p> <pre><code>private string _id; public string Id { get { return _id; } set { _id = value; } } </code></pre> <p><code>value</code> is a contextual keyword known only in the set accessor. It represents the value assigned to the property.</p> <p>Since this pattern is often used, C# provides automatically implemented properties. They are a short version of the code above; however, the backing variable is hidden and not accessible (it is accessible from within the class in VB, however).</p> <pre><code>public string Id { get; set; } </code></pre> <p>You can simply use properties as if you were accessing a field:</p> <pre><code>var obj = new MyClass(); obj.Id = "xy"; // Calls the setter with "xy" assigned to the value parameter. string id = obj.Id; // Calls the getter. </code></pre> <hr> <p>Using properties, you would search for items in the list like this</p> <pre><code>MyClass result = list.Find(x => x.Id == "xy"); </code></pre> <hr> <p>You can also use automatically implemented properties if you need a read-only property:</p> <pre><code>public string Id { get; private set; } </code></pre> <p>This enables you to set the <code>Id</code> within the class but not from outside. If you need to set it in derived classes as well you can also protect the setter</p> <pre><code>public string Id { get; protected set; } </code></pre> <hr> <p>And finally, you can declare properties as <code>virtual</code> and override them in deriving classes, allowing you to provide different implementations for getters and setters; just as for ordinary virtual methods.</p> <hr> <p>Since C# 6.0 (Visual Studio 2015, Roslyn) you can write getter-only auto-properties with an inline initializer</p> <pre><code>public string Id { get; } = "A07"; // Evaluated once when object is initialized. </code></pre> <p>You can also initialize getter-only properties within the constructor instead. Getter-only auto-properties are <strong>true</strong> read-only properties, unlike automatically implemented properties with a private setter.</p> <p>This works also with read-write auto-properties:</p> <pre><code>public string Id { get; set; } = "A07"; </code></pre> <p>Beginning with C# 6.0 you can also write properties as expression-bodied members</p> <pre><code>public DateTime Yesterday => DateTime.Date.AddDays(-1); // Evaluated at each call. // Instead of public DateTime Yesterday { get { return DateTime.Date.AddDays(-1); } } </code></pre> <p>See: <a href="https://roslyn.codeplex.com/" rel="noreferrer">.NET Compiler Platform ("Roslyn")</a><br>          <a href="https://github.com/dotnet/roslyn/wiki/New-Language-Features-in-C%23-6" rel="noreferrer">New Language Features in C# 6</a></p> <p>Starting with <a href="https://blogs.msdn.microsoft.com/dotnet/2016/08/24/whats-new-in-csharp-7-0/" rel="noreferrer">C# 7.0</a>, both, getter and setter, can be written with expression bodies:</p> <pre><code>public string Name { get => _name; // getter set => _name = value; // setter } </code></pre> <p>Note that in this case the setter must be an expression. It cannot be a statement. The example above works, because in C#, an assignment can be used as an expression or as a statement. The value of an assignment expression is the assigned value where the assignment itself is a side effect. This allows you to assign a value to more than one variable at once: <code>x = y = z = 0</code> is equivalent to <code>x = (y = (z = 0))</code> and has the same effect as the statements <code>x = 0; y = 0; z = 0;</code>.</p>

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