Notes on software and the ideas behind it

Find the meaning
behind the code.

I’m Fred Yang. I write about software—how it works, why it behaves the way it does, and the ideas that make code easier to reason about.

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Working notes / 2026

Recently mapped

Architecture, reactivity, and the hidden relationships that shape frontend systems.

Entity Framework

Get started with EntityFramework 4

We have the following option to using EntityFramework4 Using designer Model First We can design model first , then generate the sql for the model, use the sql to generate the database, and then...
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clr

Nullable notes

Nullable is value type object. But the following code can be compiled. int? x = null Isn't "null" supposed to be used with reference type, why it can be assigned with value type? It...
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vs.net

make your obsolete method invisible

When I started to use moq, there was lots example of moq that use mock.Setup method, althought these code can be compile. The this method is not shown up in intellisense popup, it turns...
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clr

When a constructor is not called

Normally, when we build a .net object, clr will call the constructor. But In a few situations, an instance of a type can be created without an instance constructor being called. In particular, calling...
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asp.net mvc

Links in asp.net

There are serveral helper class which help to generate links. //When you generate link with the same controller Html.ActionLink();
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