Refactoring

Refactoring your code involves changing the way it's written and 0:01 organized without changing the functionality. 0:03 We refactor our code to increase readability and reduce complexity. 0:07 This ultimately makes your projects easier to maintain and saves time and money. 0:11 Your results may vary but refactoring always puts a smile on my face because 0:17 I love taking something that was previously complicated And 0:21 making it easy to understand. 0:24 Let's simplify some code. 0:26 I'm gonna start with my personal favorite refactoring tool, extract method. 0:28 In my ShippingHelper class I have a method called calculateShippingCost. 0:33 I did an okay job of leaving comments as to why these things are affecting 0:37 the shipping costs. 0:41 But it still is hard to quickly understand what this method does because it has so 0:42 many lines. 0:45 We can break some of this logic out using extract method. 0:46 First off, I'm going to select my logic for the multi-item surcharge and 0:50 press control period to bring up the quick actions in refactoring menu. 0:54 Visual Studio's already detected that extract method is the only viable action. 0:58 I'll press enter to extract method and give my new method a name. 1:02 I call my new method CalculateMultiItemSurcharge and 1:06 press Enter. 1:10 Note that Visual Studio was able to determine that I am modifying my cost 1:12 variable. 1:15 And that the new method needs access to the cost of variable as well as number of 1:16 items, distance and cost. 1:20 Next let's do the same thing with our heavy item surcharge. 1:23 And finally let's do the same with our oversized box surcharge. 1:40 We are left with many small methods that perform a single task instead of a single 1:57 method that performs many tasks. 2:01 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 2:08 actually the best name for that method. 2:11 It really applies only to heavy items and 2:14 I want to rename it to CalculateHeavyItemsSurcharge, but 2:16 I'm afraid that doing so might break other methods that reference it. 2:20 Luckily for me Visual Studio knows how to check references for you and 2:23 rename them automatically. 2:27 I'll change the name of the method to CalculateHeavyItemSurcharge and 2:29 press control period. 2:33 Visual Studio shows me a diff, so I know what other lines of code I'm changing and 2:40 I press Enter to accept the change. 2:45 Rename works for renaming fields, methods, variables, properties, 2:48 name spaces, and types. 2:52 Now that I've had some time to think things over, 2:55 I want item size to appear my method signature before a number of items. 2:56 But again changing this might cause other methods that rely on this method to throw 3:00 exceptions. 3:04 Or worse, since both properties are the same type, methods that call this method 3:05 might pass in an item size as number of items and vice versa. 3:09 We can have Visual Studio modify all references by highlighting the method 3:14 pressing control period and 3:18 pressing Enter to select Change Signature then reordering our parameters as desired. 3:19 I just noticed that I have some using statements that I don't need. 3:28 I can automatically remove them by pressing Ctrl+EQ or 3:32 right clicking on my CS file and going to Organize Usings, Remove and Sort Usings. 3:35 This is important because it keeps your class files clean, but it also improves 3:45 performance on IntelliSense and compile time because of Visual Studio and 3:49 MSBuild respectively don't have to search as many name spaces. 3:53 Plus you look cool and 3:57 impress your friends with your minimalist using directives. 3:58 By using Visual Studio's refactoring tools, we clean this class up and 4:02 made it easier to understand. 4:05 It's hard for me to overstate the importance of refactoring. 4:07 You should refactor your code often and rely on Visual Studio to help you do it. 4:10