Prefixes

Control Prefix

Button btn

Label lbl

TextBox txt

ListBox lst

GroupBox grp

PictureBox img

RadioButton rad

CheckBox chk

Timer tmr

If I don't have a control listed here, make up your own appropriate prefix.

Lists and ListBoxes

Depending on your needs, you may use a ListBox to maintain a collection of data, or you may use a list to maintain the actual data behind the scenes and just keep the ListBox updated based on the underlying list (see setting the DataSource below).

You can use a ListBox to store a number of items.

If you add an item to a ListBox, it's ToString() method will be called and its string representation will be what is displayed in the ListBox.

Add an item:

The ListBox will display whatever ToString() returns for the item added to the list.

lstThings.Items.Add("Hello"); //Adds to the end of the list

lstThings.Items.Insert(2, "Hello"); //Inserts item at a specific index

You can add an entire list (eg. myList) to a ListBox as well:

lstThings.Items.AddRange(myList.ToArray());

This can also be done by setting the ListBoxes DataSource to your list, see below:

Get Items:

lstThings.SelectedIndex //Provides the index of the selected item in the list

lstThings.SelectedItem //Provides the value of the selected item in the list

Remove Items:

lstThings.Items.RemoveAt(0); //Removes whatever is at index 0

lstThings.Items.RemoveAt(lstThings.SelectedIndex); //Removes selected item by its index

lstThings.Items.Remove(lstThings.SelectedItem); //Removes selected item by its value

lstThings.Items.Remove("Hello"); //Removes "Hello" from ListBox

lstThings.Items.Clear(); //Removes everything from ListBox

You can also bind a list to a ListBox.

This may be better if you are maintaining Lists behind the scenes with your data.

List<string> names = new List<string>();

... //Add some names to the list

lstThings.DatSource = null; //Clears any previous DataSource

lstThings.DataSource = names; //Populates the ListBox with items from names.

//ToString() will be used to populate the ListBox

PictureBoxes

Changing the Image in a PictureBox

imgTrilobyte.Image = Properties.Resources.itemFromResources;

Adding Forms

Project->Add Form-> Give the form a name: FormAboutExample

To make a new Form:

FormAboutExample frmAboutExample = new FormAboutExample();

To Show The Form:

frmAboutExample.Show(); // User will be able to switch between forms

//Inside the new Form:

this.Close(); // Will allow the Form to close itself

or

frmAboutExample.ShowDialog(); // Program halts here until the Form is closed

//Inside the new Form:

this.Dispose(); // Will allow the Form to close itself.

To Hide a Form:

frmAboutExample.Hide();

MessageBoxes

The easiest way to pop up a simple OK MessageBox to convey a message is:

MessageBox.Show("MessageBox Text Goes Here");

For more like using different types of MessageBoxes and detecting which Button was clicked see here (or do an internet search yourself):

https://www.c-sharpcorner.com/UploadFile/mahesh/understanding-message-box-in-windows-forms-using-C-Sharp/

Open and Close FileDialog Boxes

Create a DialogBox either in the designer or using code:

OpenFileDialog FileDialogName = new OpenFileDialog(); //Same with SaveFileDialog

Use an If statement so that it only attempts file access if the user clicks OK:

if (FileDialogName.ShowDialog() == DialogResult.OK)

{

//Code to read/write file goes here, see FILEIO.

//You can get the name of the file selected by accessing the FileName property:

//FileDialogName.FileName

}

Properties

Here are some initial properties you may wish to set:

//Allows you to specify a starting directory

FileDialogName.InitialDirectory = "c:\\";

//Allows you to specify different filter settings that can be selected in the Dialog box.

FileDialogName.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";

//Determins which filter that you provided is the default filter

FileDialogName.FilterIndex = 2; //All files filter would be default in this case

FileDialogName.FilterIndex = 1; //txt files filter would be default in this case

//Opens dialog box to whatever previous directory was

FileDialogName.RestoreDirectory = true;