/SOY/ACADEMY
LEARNING PROGRAMMING - C#
LESSON 1: Value data types, convert method, parse/tryparse
>Value data types 
<int
Stores whole number values, typically within the range of -2³¹ to 2³¹ - 1
^Example: int a = 5;
<float
Stores decimal numbers. Needs suffix f or F when entering value
^Example: float a = 2.5f;
2. <double 
Stores decimal numbers with higher precision than float. Useful in calculations
^Example: double a = 5.8;

3.<char
Is used to store a single Unicode character. The value is enclosed in single quotes (' '). It occupies 2 bytes in memory.
^Example: char a = 'A';
4. <bool
It is used to store logical values such as true or false. It is mainly used in conditional statements. It helps in decision-making within programs
^Example: bool a = true;
>Reference data types
These store the reference (memory address) of the data instead of the actual value. Multiple variables can refer to the same data in memory. Any changes made through one variable will affect the other variables referring to the same object
<string
Used to store a sequence of characters (text). It is a reference data type in C#. Strings are immutable, meaning their value cannot be changed after creation
^Example: string a = "fuggem jardee";
2.<array
Used to store multiple values of the same data type. Elements are stored in contiguous memory locations
^Example: int[] arr = {1, 2, 3};
3.<object
The base type of all data types in C#. It can store values of any type using boxing [].
^Example: int[] arr = {1, 2, 3};
^Console.WriteLine(arr[0]);
Since the object 0 in our array arr is 1, the console output from WriteLine operation will be 1
>Pointer data type
These store the memory address of variables instead of actual values
Pointer (int* p) will atore the memory adress of a valuable:
^int n = 20;
^int* p = &n;
>Convert.
Convert. is a method when you convert data into another data type. For instance:
<string a = "5"; 
<string - text data
<int b = Convert.ToInt32(a);
By converting string a into Int data, we turned its' value "5" from text data into number data, so now int b = 5 instead of text "5". The PC doesn't see the symbols the same as we do. To fully grasp the possibilities of Convert., we need to look up all the data types
>parse
An operation of converting a string (text data) into another data type. Kinda similar to Conver. class
^Example: string numbers = "123";
^int a = int.Parse(numbers);
with int.Parse, we change the text "123" into an actual number value, so int a = 123.
<NOTE! When changing data types, you MVST look at the value - if the value doesn't match the data rype you're trying to convert it into, you will get an Exception - an error, basically. Example: string b = "123abc"; will not be able to be converted to a number because there are letters in the string b's text value. Same probably goes for Convert., if anyhpono can confirm this
>tryparse
Like parse, it concerts strings into other data types, but works a bit differently - tryparase takes 2 parameters to do its' job:
<1)The string we want to parse
<2)The data type we want the string value to change into
^Example: string a = "1";
^int b;
^int.TryParse(a, out b);
We have the string a that has text value "1", and int b that has no assigned value. By using int.TryParse, we take string a's text value (a), and then parce in into a whole number - int value (thats why we write int before .TryParse). After the value is successfully parced to the required data type, it will be assigned to int b - because we wrote (out b). So now int b will contain the resuilt of our tryparse
<NOTE! Unlike parse, if tryparse sees that the string value cannot be correctly changed to the required data type - it will create a failure message, unlike parse and its' exception. The difference is - with tryparse your program will continue working while you receive failure messages, and with parse the programm will stop
>operators
Symbols that perform operations on variables and values. A value/variable that gets an operation performed on it is called an operand.
<Types of operators:
<Unary
<Binary
<Ternary
>Arithmetic operations
They use binary operators:
<Addition uses +
<Subtraction uses -
<Multiplication uses *
<Division uses /
<Modulo division uses % - it returns the remainder of a division from two ints
^Example of an arithmetic operation:
^int a = 5;
^int b = 6;
^int c = a + b;
Arithmetic operation a + b will add their values up, making 11. So now int c will store the value 11
>increment/decrement
Increment (++) is an operator that increases the numeric value of a variable by 1, while decrement (–) decreases it by 1. These operators are unary - they require only 1 variable to complete an operation 
^Example: int a = 1;
a++;
a–;
By using a++, we increased the value of int a by 1, resulting in 2. And by using a– afterwards, we decreased that value by 1, going back to 1
<NOTE! There are two forms of increment/decrement:
<Postfix form: operator is placed after the variable
^a++ or a–
<Prefix form: operator is placed before the variable
^++a or –a
The difference between these forms is: postfix form has lower priority, being complete after other operations. While prefix form has higher priority, being complete before other operations.
^Example: int a = 1;
^Console.WriteLine(a++);
We use Console.WriteLine to write the value of int a increased by 1 in the console. But since we used the postfix form, the console will show us 1 instead of 2, because a++ has lower priority than Console.WriteLine.
On the contrary, Console.WriteLime(++a) will show us 2, because prefix form ++a will have priority over Console.WriteLine, being complete first before showing up in the console