Strings (text), numbers, characters, bool, null, default

Strings contain text. More info: C# strings, recipe strings and characters.

string s1 = "text";
string s2 = ""; //empty string
string s3 = null; //no string. Not the same as "".
print.it("this is a \"string\"\r\n\twith \\ escape sequences");

Frequently used escape sequences: \" - " \\ - \ \t - tab \n - newline \r\n - Windows newline (2 characters) \0 - character code 0

To avoid writing many escape sequences, use verbatim strings or raw strings.

string path = @"C:\folder\file"; //instead of "C:\\folder\\file"
string verbatim1 = @"multiline
string";
string verbatim2 = @"abc ""def"" gh"; //for " use ""

string raw1 = """raw single-line string without any escape sequences""";
string raw2 = """
raw multi-line string
without any escape sequences
""";
string raw3 = """"another """raw""" string """";

To easily create strings with variables, can be used interpolated strings, operator + and other ways. More info in recipe string formatting.

string s4 = $"ab {s1} cd {path} ef";
string s5 = @$"ab {s1}
cd {path} ef";
string s6 = $"""ab {s1} cd""";
string s7 = $$"""ab {{s1}} {cd}""";

string s8 = "ab " + s1 + " cd";

Strings consist of characters. Characters also can be used alone.

char c1 = 'A';
char c2 = ' '; //space
char[] a1 = { '\t', '\r', '\n', '\"', '\'', '\\', '\0' }; //escape sequences like in strings

Integer numbers are numbers like 10 but not like 1.5.

int i1 = 10, i2 = -20;
int i3 = 2000000000; //or 2_000_000_000
int i4 = 0x10; //hexadecimal 16
int i5 = unchecked((int)0xFFFFFFFF); //sorry, simple values 0x80000000...0xFFFFFFFF are considered too big for int
uint u1 = 0xFFFFFFFF; //unsigned int
var u2 = 5u; //uint (suffix u)
var k1 = 5L; //long (suffix L)
long k2 = 9_223_372_036_854_775_807; //max long integer value
print.it(int.MaxValue, int.MinValue); //for max/min values it's better to use these constants

Floating-point numbers can be non-integer and can hold larger values.

double d1 = 3.14;
double d2 = 0.5; //or .5
double d4 = -2e6; //-2000000
double d5 = 3.5e-3; //0.0035
var d6 = 5d; //double (use suffix d)
print.it(double.MaxValue, Math.PI); //use constants
float f1 = 0.5f; //float is smaller (32-bit instead of 64-bit) and less precise
decimal g1 = 10.1234m; //the largest numeric type

Boolean values can be either true or false.

bool b1 = true;
bool b2 = false;
bool? b3 = null; //nullable bool can be true, false or null

To specify default value of that type, use keyword default. For reference types, nullables and pointers also can be used null.

string sn = null; //string is a reference type (class)
DateTime dt = default; //value type (struct)
bool? bn = null; //nullable value type