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General C# Cheat Sheet (DRAFT) by

Cheatsheet for C#

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Data Types

byte
8-bit unsigned integer
0 to 255
 
byte value = 255;
int
32-bit signed integer
-2,147­,48­3,648 to 2,147,­483,647
 
int value = 3;
float
32-bit Single­-pr­ecision floating point type
-3.402­823e38 to 3.4028­23e38
 
float value = 6.3F;
char
16-bit single Unicode character
Any valid character, e.g. a,*, \x0058 (hex), or\u0058 (Unicode)
 
char value = 'H';
bool
8-bit logical true/false value
True or false.
 
bool value = true;
string
A sequence of Unicode characters
Combin­ation of charac­ters.
 
string value = "­Hel­lo";

Type Conversion Methods

Conver­t.T­oBo­ole­an(­var­iable);
 
Conver­t.T­oBy­te(­var­iable);
 
Conver­t.T­oCh­ar(­var­iable);
 
Conver­t.T­oDa­teT­ime­(va­ria­ble);
 
Conver­t.T­oIn­t32­(va­ria­ble);
 
Conver­t.T­oSt­rin­g(v­ari­able(;

Naming Conven­sions

Class
MyClass
Method
MyMethod
Local variable
myLoca­lVa­riable
Private variable
_myPri­vat­eVa­riable
Constant
MyConstant

Statements

if-else
 
if (true) {...} else if (true) {...} else {...}
switch
 
switch (var) { case 1: break; default: break; }
for
 
for (int i =1; i < 5; i++) {...}
foreach
 
foreach (int item in array) {...}
while
 
while (true) {...}
do-while
 
do {...} while (true);
try-ca­­tc­h­-­fi­­nally
 
try {...} catch (Exception e) {...} catch {...} finally {...}

Arrays and Methods

int[] array = new int[] {1, 2, 3};
Defines a new array.
 
int[] array = {1, 2, 3};
Defines a new array.
 
var array = new int[] {1, 2, 3};
Defines a new array.
 
int[] array = new int[3];
Defines a new array.
 
int[,] array2D = new int[,] { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } };
Defines a new two dimens­ional array.
 
int[,] array2Da = new int[4, 2] { { 1, 2 }, { 3, 4 }, { 5, 6 }, { 7, 8 } };
Defines a new two dimens­ional array with dimensions specified.
 
int[, ,] array3D = new int[,,] { { { 1, 2, 3 }, { 4, 5, 6 } }, { { 7, 8, 9 }, { 10, 11, 12 } } };
Defines a new three dimens­ional array.
 
int[, ,] array3Da = new int[2, 2, 3] { { { 1, 2, 3 }, { 4, 5, 6 } }, { { 7, 8, 9 }, { 10, 11, 12 } } };
Defines a new three dimens­ional array with dimensions specified.
 
array.G­et­Len­gth­(int32)
Gets a 32-bit integer that represents the number of elements in the specified dimension of the Array.

Classes

Class
 
public class Animal {...}
Makes a new class named Animal.
Inheri­­tance
 
public class Dog:Animal {...}
Inherits from a class. Example every animal has a size, but not every animal is the same size.
Constr­­uctor (no parame­­ters)
 
public Dog() {...}
Method in a class that activates when the class is instan­ciated.
Constr­­uctor (one parameter)
 
public Dog (string var) {...}
Method in a class that activates when the class is instan­ciated with parame­ters.
Decons­tructor (cannot have parame­ters)
 
~Dog () {...}
Method in a class that activates when the class is destroyed.
Call method
 
Method­Name();
Calls a custom or already existing method.

Lists and Methods

List<T­ype> listName = new List<T­>();
Declares a new list.
 
listNa­me.C­ount
Gets the number of elements contained in the List<T­>.
 
listNa­me.A­dd(T);
Adds an object to the end of the List<T­>.
 
listNa­me.C­le­ar();
Removes all elements from the List<T­>.
 
listNa­me.C­on­tai­ns(T);
Determines whether an element is in the List<T­>.
 
listNa­me.E­qu­als­(Ob­ject);
Determines whether the specified object is equal to the current object.
 
listNa­me.I­nd­exO­f(T);
Searches for the specified object and returns the zero-based index of the first occurrence within the entire List<T­>.
 
listNa­me.R­em­ove(T);
Removes the first occurrence of a specific object from the List<T­>.
 
listNa­me.R­em­ove­At(­Int32);
Removes the element at the specified index of the List<T­>.

Access Modifiers

public
Accessible by any other code in the same assembly or another assembly that references it.
 
public int ...;
private
Only accessible by code in the same class or struct.
 
private int ...;
protected
Only accessible by code in the same class or struct, or in a derived class
 
protected int ...;

Other Modifiers

abstract
Indicates that a class is intended only to be a base class of other classes.
 
abstract class Shape { ... }
async
Indicates that the modified method, lambda expres­­sion, or anonymous method is asynch­­ro­nous. (This is used if a function needs to have an delay or await)
 
private async void Task() { ... }
const
Specifies that the value of the field or the local variable cannot be modified. (You cannot say X = 1; later in the program if it's a const)
 
const int X = 0;
event
Declares an event. Mostly used in combin­ation with an delegate.
 
public event Sample­Eve­ntH­andler Sample­Event;
delegate
Declares a delegate. Mostly used in combin­ation with an event.
 
public delegate void Sample­Eve­ntH­and­ler­(object sender, Sample­Eve­ntArgs e;
new
The new operator creates a new instance of a type.
 
public Random random = new Random();
override
Provides a new implem­­en­t­ation of a virtual member inherited from a base class.
 
public override void ToString() { ... }
readonly
Declares a field that can only be assigned values as part of the declar­­ation or in a constr­­uctor in the same class. (Same as const, you cannot change the value later)
 
private readonly int value = 6;
static
Declares a member that belongs to the type itself instead of to a specific object.
 
static int = 7;

Assigment Operators

=
Simple assign­ment.
+=
Addition assign­ment.
-=
Subtra­­ction assign­ment.
*=
Multip­­li­c­ation assign­ment.
/=
Division assign­ment.
%=
Remainder assign­ment.
&=
AND assign­ment.
|=
OR assign­ment.

Comparison Operators

<
Less than.
<
Greater than.
<=
Less than or equal to.
>=
Greater than or equal to.
==
Equal to.
!=
Not equal to

Arithmetic Operators

+
Add numbers.
-
Subtract numbers.
*
Multiply numbers.
/
Devide numbers.
%
Compute remainder of division of numbers.
++
Increases integer value by 1.
--
Decreases integer value by 1.

Logical Operators

&&
Logical AND.
||
Logical OR.
!
Logical NOT.

Other Operators

&
Returns the address of a variable.
*
Pointer to a variable.
? :
Condit­­ional expres­sion.
 
is this condition true ? yes : no;
is
Determines whether an object is of a specific type.
as
Cast without raising an exception if the cast fails.

Console

Consol­e.C­lear();
Clears the console buffer and corres­ponding console window of display inform­ation.
 
Consol­e.R­ead­Key();
Obtains the next character or function key pressed by the user. The pressed key is displayed in the console window.
 
Consol­e.R­ead­Line();
Reads the next line of characters from the standard input stream.
 
Consol­e.W­rit­eLi­ne();
Writes the current line terminator to the standard output stream.

Misc

//
Adds a comment.
#region RegionName - #endregion
Makes a region (for code colapsing) and ends it with endregion.