Adding items to this controls in .Net is very easy. To demonstrate that we will create a simple project with the following controls:
- ListBox (name: listBox1)
- ComboBox (name: comboBox1)
- TextBox (name: textBox1)
- Button (text: Add)
So, drag this controls from the toolbox and drop them on the main form one by one. Make a form like this

Now double click on the button, it will create a button click event. Insert this code there
listBox1.Items.Add(textBox1.Text); comboBox1.Items.Add(textBox1.Text); textBox1.Clear();
Now, write something in the text box and then click the button. The text you entered in the textBox1 will be inserted as item in the listBox1 and comboBox1, and the textBox1 text will be cleared.




