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    <p>There's no way around it, the C# specification explicitly says that <a href="http://msdn.microsoft.com/en-us/library/ms364047(VS.80).aspx#cs3spec_topic5" rel="noreferrer">"It is not possible for an object or collection initializer to refer to the object instance being initialized."</a></p> <p>As for why it's impossible, I suspect that there's just no nice way to implement it. We want some syntactic sugar equivalent to</p> <pre><code>var temp = new TestClass(); temp.Id = 1; temp.SomeProperty = SomeMethod(temp); x = temp; </code></pre> <p>We just need a keyword to refer to <code>temp</code> within the initializer, but none is easily available. We can't use <code>this</code> because it already means something outside the initializer. Should <code>SomeProperty = this.SomeMethod(this)</code> be equivalent to <code>temp.SomeProperty = this.SomeMethod(temp)</code> or <code>temp.SomeProperty = temp.SomeMethod(temp)</code>? The second is consistent, but then what happens if we need the first?</p> <p>We could try to use <code>x</code>, though we can only pick a name if the new object is immediately assigned to a variable. However, we now can't refer to the old value of <code>x</code> inside the initializer, doing the equivalent of <code>temp.SomeProperty = SomeMethod(x)</code>.</p> <p>We could reuse the <code>value</code> keyword from property setters. This sounds good since <code>value</code> already stands in for the missing parameter if you consider a property getter to be syntactic sugar for a <code>set_SomeProperty(value)</code> method. Using it to also refer to the missing variable in the object initializer looks promising. However, we could be creating this object inside a property setter, in which case <code>value</code> is already being used, and we need to be able to do <code>temp.SomeProperty = SomeMethod(value)</code>.</p> <p>It looks like we'll have to create a new keyword just for this purpose, maybe <code>newthis</code>. However, this is a breaking change to the language because any code that has a variable called <code>newthis</code> doesn't work any more. Microsoft generally needs a really good reason to introduce breaking changes, so it's better to forbid access to the object being initialized.</p>
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    1. COIt is interesting that C# does not support this because VB does. Something like new MyObject() with {.Property1 = "x", .Property2=.Property1+"y"} does work. Usually the language functionality is very similar but it appears in this case it is not. I have a rather complex LINQ query that I just can't seem to convert to C# due to this limitation.
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