Basic C# Clearly Explained

Main Idea: Console applications are the easiest place to begin learning C# programming

Key Points:

1. Understand what a console application is
2. Learn how to create a console application project in Visual Studio Community 2015
3. Delete the default code and replace it with a simpler version
4. Understand the simplified code in detail
5. Learn how run the code
6. Learn the meaning of the green and yellow lines that show in the code editor window

Main Idea: A program that can produce output is immediately more useful to a user

Key Points:

1. Understand the purpose of using System;
2. Add one line of code to the body of Main
3. Understand the concept of a string as a sequence of characters between double quotes
4. Understand how to change the environment font

Main Idea: C# comes with a large amount of functionality already prebuilt

Key Points:

1. Name spaces are used to organize code
2. Names spaces store classes
3. Classes store methods
4. IntelliSense makes Visual Studio Community 2015 easier to use by suggesting what functionality is available as we type code

Main Idea: Tool tips provide immediate access to a wealth of contextually relevant information

Key Points:

1. Create a simple console application
2. Add one line of code to print output
3. Hover mouse over WriteLine, and go through the tool tip information that shows

Main Idea: Write less code, but accomplish the same results by adding the word "static" to a using statement

Key Points:

1. Replace the using System; statement with using static System.Console;
2. Understand how changing the using statement impacts code that can print output

Main Idea: Visual Studio has many ways of accessing project files easily and quickly

Key Points:

1. View the files that make a project by opening Windows file explorer
2. Learn how to launch a project from the folder where it's stored
3. Learn how to launch a solution from the folder where it's stored
4. Understand that a solution can consist of multiple projects

Main Idea: Variables are used to represent changing, or unknown quantities

Key Points:

1. Understand the need for variables
2. Become familiar with a possible mental model for representing variables
3. Understand how to declare a variable, and set its value
4. Learn how to use string interpolation and why the dollar symbol is needed
5. Understand how to print a variable value using string interpolation

Main Idea: A programmer should never feel uncertain about the values of variables as a program runs

Key Points:

1. Understand how to launch a program through the debugger
2. Understand how the debugger helps to see variable values
3. Become familiar with the concept of default values and how to see them in the debugger

Main Idea: C# has a variety of data types can be used together to produce accurate descriptions of objects

Key Points:

1. Understand how to create and set multiple variables in C#
2. Become familiar with the concept of camel casing in variable names

Main Idea: There are many key combinations that make using Visual Studio much more efficient

Key Points:

1. The tab key can move a block of highlighted code right
2. The shift+tab key combination can move a highlighted block of code left
3. Ctrl+M+P can be used to hide the little minus signs that allow us to collapse code
4. Pressing alt and dragging can highlight a rectangle of code
5. A context-sensitive menu is one that shows different options based on where a click occurs

Main Idea: Visual Studio has a huge database of information already present, so time can be saved searching the Internet

Key Points:

1. Add a line of code that generates an error
2. Understand how to take a step towards understanding the error better
3. Fix the error so the code works
4. Understand that some errors prevent a program from being built, and some error sdo not prevent a program from being built

Main Idea: C# has the same arithmetic operators, like addition, that we learned to use in school for basic math

Key Points:

1. + symbol allows us to produce the sum of two values
2. - symbol allows us to produce the difference of two values
3. * symbol allows us to multiply two values
4. Understand the purpose of tool tips that show when cursor is hovered over an operator

Main Idea: To save time creating variables, it's possible to embed calculations directly in WriteLine

Drawback: The values calculated in WriteLine are not saved to variables, so they can't be used again

Key Points:

1. Create two variables of type decimal
2. Display the result of multiplying them directly inside WriteLine

Main Idea: Understanding the difference in results produced by the slash symbol

Key Points:

1. Dividing two integer numbers using the slash symbol produces one result
2. Dividing two double numbers using the slash symbol produces a different result

Main Idea: Understanding the difference between results produced when using the / and % for division

Key Points:

1. The slash division symbol tells how many times whole the bottom of a division goes into the top
2. The percent symbol tells the remainder of a division

Main Idea: A truly useful program might have to evaluate complex mathematical expressions

Key Points:

1. The evaluation of mathematical expressions can be controlled using grouping symbols
2. Mathematical expressions can be as simple or as complex as necessary
3. Create and run code to find the average of three salaries

Main Idea: Replace long expressions with more compact ones to save typing and space

Key Points:

1. Understand how to add to and subtract from a variable, and save back to the same memory location
2. Understand how to multiply and divide a variable, and save back to the same memory location
3. Understand the relationship between x=x+1 and x+=1 and similar assignment statements

Main Idea: C# has two very compact operators that allow us to grow a variable value

Key Points:

1. Understand the operation of ++x, which is the pre-increment operator
2. Understand the operation of x++, which is the post-increment operator
3. Understand how these operators execute inside WriteLine

Main Idea: Some things do not change, and C# allows us to represent these in code

Key Points:

1. Understand why constants are needed
2. Create a constant in C#
3. Understand how to make use of a constant in a calculation
4. Understand what happens when an attempt is made to change a constant value

Main Idea: Variables have a life cycle, just like everything else, and understanding this cycle leads to fewer errors

Key Points:

1. Understand the life cycle of a simple variable
2. Become familiar with the concept of variable scope, or context
3. Become familiar with the consequences of trying to reach a variable outside its scope

Main Idea: It's possible to format output so it looks as best as possible to users

Key Points:

1. C# has format specifiers like C for currency
2. Format specifiers are embedded into output
3. The logic presented in the video applies to most format specifiers

Main Idea: The var keyword, in many cases, can recognize the data type of a variable automatically

Key Points:

1. The var keyword can recognize the data type of a variable
2. The var keyword can recognize the data type of a quantity that results from a calculation
3. To check on the data type of an implicitly typed variable, hover your mouse over var

Main Idea: Users expect to be able to interact with programs by entering input and receiving output

Key Points:

1. Understand how to show a prompt
2. Understand how to read string input
3. Learn how to call a method on the input
4. Create an example of output
5. Understand how to ensure data types on the left side of "=" are equal

Main Idea: Reading numerical input requires a conversion step

Key Points:

1. Read input first with ReadLine()
2. Understand how to pass a variable into a method for processing
3. Understand why double.Parse() is needed
4. Understand how to ensure data types on the left and right sides of "=" match

Main Idea: Method nesting allows us to create less code

Drawback: Method nesting prevents us from saving variable values at each stage

Key Points:

1. Understand how to replace two lines of code with one line of code
2. Understand how to be sure the nested and nesting methods are compatible

Main Idea: Method chaining allows us to process input using compactly written code

Drawback: Intermediate processing results are not saved in variables

Key Points:

1. Understand how to replace multiple lines of code with a single line of code
2. Understand the reason for using the methods in this particular example
3. Understand that the data type of the value returned by the last method should match the data type of a variable

Main Idea: Data conversions allow one type of data to be converted to another type so it's easier to work with it

Key Points:

1. Learn how to use the Read method to read an integer
2. Understand how to convert an integer to a character
3. Become familiar with the concept of an explicit data cast

Key Points:

1. C# remains popular as a programming language
2. There are many jobs in C#
3. It's always a great tool for tinkering and learning more
4. Please note the 20 hour course is considerably more challenging