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James A. Michener once said “I'm not a very good writer, but I'm an excellent rewriter”. Learn how to get Visual Studio to rewrite your code for you using powerful refactoring tools.
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Refactoring your code involves
changing the way it's written and
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organized without changing
the functionality.
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We refactor our code to increase
readability and reduce complexity.
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This ultimately makes your projects easier
to maintain and saves time and money.
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Your results may vary but refactoring
always puts a smile on my face because
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I love taking something that
was previously complicated And
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making it easy to understand.
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Let's simplify some code.
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I'm gonna start with my personal favorite
refactoring tool, extract method.
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In my ShippingHelper class I have
a method called calculateShippingCost.
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I did an okay job of leaving comments
as to why these things are affecting
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the shipping costs.
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But it still is hard to quickly understand
what this method does because it has so
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many lines.
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We can break some of this logic
out using extract method.
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First off, I'm going to select my
logic for the multi-item surcharge and
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press control period to bring up
the quick actions in refactoring menu.
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Visual Studio's already detected that
extract method is the only viable action.
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I'll press enter to extract method and
give my new method a name.
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I call my new method
CalculateMultiItemSurcharge and
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press Enter.
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Note that Visual Studio was able to
determine that I am modifying my cost
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variable.
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And that the new method needs access to
the cost of variable as well as number of
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items, distance and cost.
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Next let's do the same thing
with our heavy item surcharge.
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And finally let's do the same
with our oversized box surcharge.
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We are left with many small methods that
perform a single task instead of a single
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method that performs many tasks.
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This makes our code easier to read and
easier to modify.
2:04
You know, now that I'm looking at
it CalculateWeightSurcharge isn't
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actually the best name for that method.
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It really applies only to heavy items and
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I want to rename it to
CalculateHeavyItemsSurcharge, but
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I'm afraid that doing so might break
other methods that reference it.
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Luckily for me Visual Studio knows
how to check references for you and
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rename them automatically.
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I'll change the name of the method
to CalculateHeavyItemSurcharge and
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press control period.
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Visual Studio shows me a diff, so I know
what other lines of code I'm changing and
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I press Enter to accept the change.
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Rename works for renaming fields,
methods, variables, properties,
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name spaces, and types.
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Now that I've had some
time to think things over,
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I want item size to appear my method
signature before a number of items.
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But again changing this might cause other
methods that rely on this method to throw
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exceptions.
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Or worse, since both properties are the
same type, methods that call this method
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might pass in an item size as
number of items and vice versa.
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We can have Visual Studio modify all
references by highlighting the method
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pressing control period and
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pressing Enter to select Change Signature
then reordering our parameters as desired.
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I just noticed that I have some
using statements that I don't need.
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I can automatically remove
them by pressing Ctrl+EQ or
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right clicking on my CS file and going to
Organize Usings, Remove and Sort Usings.
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This is important because it keeps your
class files clean, but it also improves
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performance on IntelliSense and
compile time because of Visual Studio and
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MSBuild respectively don't have
to search as many name spaces.
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Plus you look cool and
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impress your friends with your
minimalist using directives.
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By using Visual Studio's refactoring
tools, we clean this class up and
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made it easier to understand.
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It's hard for me to overstate
the importance of refactoring.
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You should refactor your code often and
rely on Visual Studio to help you do it.
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