Basics

C# is case-sensitive, including its variable and method names.

Move Line Up/Down - ALT + UP/DOWN

Copy Line - ctrl+c with nothing selected, then paste

Comments

/* 
   This is another style of a comment.
   It allows multiple lines.
*/

//  alert
MessageBox.Show("Rob is amazing.");

// labelbox
label1.Text = "Hellow World!";

Variables

int robsNumber = 3;
double robsBigNumber = 3.333333;
decimal robsDecimal = 67.83m;
string robsString = "Rob is amazing";
bool days_ok = false;

// constant
const int PI = 3.14;

// private variabe
private string name = "Rob Secrets";

// change to decimal - this doesnt work.
int wholeNumber 33;
decimal moneyNumber = 4500m;
wholeNumber = (int) moneynumber;

try catch

try
{
    //code
catch (Exception ex)
{
    MessageBox.Show(ex.Message);
}

Parseing

//parsing string to a number
double myVar1 = double.Parse(textBox1.Text);

// if parse
if (int.TryParse(tb_input_days, out tb_input_days_int))
{
    days_ok = true;
}

Hide Show Elements

pictureBox1.Visible = false;
pictureBox2.Visible = true;

// close the window
this.Close();

Label

//clear a label
label2.Text = "";

// do a calculation and output to a label
label_main_output.Text = ((weight * 703)/height).ToString();

Textbox

// store string
string lname = textBox_lname.Text;

// store  number
double cost = double.Parse(tb_cost.Text);
int height = int.Parse(textBox_h.Text);

// focus
textBox_numberOfPackages.Focus();

// get string, concatenate, print
string fname = tb_fname.Text;
string lname = tb_lname.Text;
string mname = tb_mname.Text;
string title = tb_title.Text; 
label_main.Text = title + " " + fname + " " + mname + " " + lname;

// get number, calculate, print
int speed = int.Parse(tb_speed.Text);
label_main_output.Text = (speed * 12) + " mph";

Shortcuts

a = a + b;
a += b;

Change Colors

messageLable.BackColor = Color.Black;
messageLable.ForeColor = Color.Yellow;

Random Number

private int randomNumber()
{
    Random rand = new Random();
    int number = rand.Next(100);
    return number;
}