ListBox_MultiSelection

namespace ListBox_MultiSelection
{

    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            object[] names = { "Sara", "Bill", "Martin", "Susan", "Don" };
            listBox1.Items.AddRange(names);
        }

        private void btnGetSelectedItems_Click(object sender, EventArgs e)
        {
            //get selected items
            ListBox.SelectedObjectCollection sItems = listBox1.SelectedItems;
            txtDisplay.Clear();
            foreach (object item in sItems)
            {
                txtDisplay.AppendText(item + "\n");
            }
        }

        private void btnAddNum_Click(object sender, EventArgs e)
        {
            double newValue = double.Parse(txtNumber.Text);
            listBoxDouble.Items.Add(newValue);
           
        }

        private void btnRemoveNum_Click(object sender, EventArgs e)
        {
            for (int i = listBoxDouble.SelectedIndices.Count - 1; i >= 0; i--)
            {
                listBoxDouble.Items.RemoveAt(listBoxDouble.SelectedIndices[i]);
            }
        }

        private void btnGetAvg_Click(object sender, EventArgs e)
        {
            txtAverage.Clear();
            double average = 0;
            ListBox.SelectedObjectCollection selectedItems = listBoxDouble.SelectedItems;
            foreach (object itemValue in selectedItems)
            {
                average += Convert.ToDouble(itemValue);
            }
            average /= listBoxDouble.SelectedItems.Count;
            txtAverage.Text = average.ToString();
        }

        private void btnCut10_Click(object sender, EventArgs e)
        {
            //lstCut10Percent.ClearSelected(
            double reducedValue;
            ListBox.SelectedIndexCollection selectedIndicies = listBoxDouble.SelectedIndices;
            foreach (int index in selectedIndicies)
            {
                reducedValue = Convert.ToDouble(listBoxDouble.Items[index]) * 0.9;
                listBoxDouble.Items[index] = reducedValue;
                listBoxDouble.SetSelected(index, true);
            }
        }
    }
}
//Lab
//Add a second listbox. Populate it with at least 10 doubles. 
//Provide gui to add new value
//
//Provide a way to remove the selected value or values

//add gui (button, label, textbox) to compute and display the average
//value of the selected values.
//and a button that cut 10 percent from each value
//that is selected.

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