ItemCheckEventArgs.CurrentValue Property

 
System_CAPS_noteNote

The .NET API Reference documentation has a new home. Visit the .NET API Browser on docs.microsoft.com to see the new experience.

Gets a value indicating the current state of the item's check box.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public CheckState CurrentValue { get; }

Property Value

Type: System.Windows.Forms.CheckState

One of the CheckState values.

This property enables you to determine the check state of the specified item in the CheckedListBox before the check state change to apply is made.

The following code example demonstrates a checked ListView control that handles the ListView.ItemChecked event. The method uses the CurrentValue and Index properties of the ItemCheckEventArgs object to retrieve and tally the price of the menu items selected. To run this example paste the following code in a form containing a ListView named ListView1 and a TextBox named Textbox1. Call the InititalizeListView method from the form's constructor or Load method. Ensure all events are associated with their event-handling methods.

private void InitializeListView()
{
	this.ListView1 = new System.Windows.Forms.ListView();

	// Set properties such as BackColor and DockStyle and Location.
	this.ListView1.BackColor = System.Drawing.SystemColors.Control;
	this.ListView1.Dock = System.Windows.Forms.DockStyle.Top;
	this.ListView1.Location = new System.Drawing.Point(0, 0);
	this.ListView1.Size = new System.Drawing.Size(292, 130);
	this.ListView1.View = System.Windows.Forms.View.Details;
	this.ListView1.HideSelection = false;

	// Allow the user to select multiple items.
	this.ListView1.MultiSelect = true;

	// Show CheckBoxes in the ListView.
	this.ListView1.CheckBoxes = true;

	//Set the column headers and populate the columns.
	ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable;

	ColumnHeader columnHeader1 = new ColumnHeader();
	columnHeader1.Text = "Breakfast Choices";
	columnHeader1.TextAlign = HorizontalAlignment.Left;
	columnHeader1.Width = 146;

	ColumnHeader columnHeader2 = new ColumnHeader();
	columnHeader2.Text = "Price Each";
	columnHeader2.TextAlign = HorizontalAlignment.Center;
	columnHeader2.Width = 142;

      	this.ListView1.Columns.Add(columnHeader1);
	this.ListView1.Columns.Add(columnHeader2);

	string[] foodList = new string[]{"Juice", "Coffee", 
		"Cereal & Milk", "Fruit Plate", "Toast & Jelly", 
		"Bagel & Cream Cheese"};

	string[] foodPrice = new string[]{"1.09", "1.09", "2.19", 
		"2.79", "2.09", "2.69"};

	int count;

	// Members are added one at a time, so call BeginUpdate to ensure 
	// the list is painted only once, rather than as each list item is added.
	ListView1.BeginUpdate();

	for(count = 0; count < foodList.Length; count++)
	{
		ListViewItem listItem = new ListViewItem(foodList[count]);
		listItem.SubItems.Add(foodPrice[count]);
		ListView1.Items.Add(listItem);
	}

	//Call EndUpdate when you finish adding items to the ListView.
	ListView1.EndUpdate();
	this.Controls.Add(this.ListView1);
}
double price = 0.0;

// Handles the ItemCheck event. The method uses the CurrentValue
// property of the ItemCheckEventArgs to retrieve and tally the  
// price of the menu items selected.  
private void ListView1_ItemCheck1(object sender, 
	System.Windows.Forms.ItemCheckEventArgs e)
{
	if (e.CurrentValue==CheckState.Unchecked)
	{
		price += Double.Parse(
			this.ListView1.Items[e.Index].SubItems[1].Text);
	}
	else if((e.CurrentValue==CheckState.Checked))
	{
		price -= Double.Parse(
			this.ListView1.Items[e.Index].SubItems[1].Text);
	}

	// Output the price to TextBox1.
	TextBox1.Text = price.ToString();
}

.NET Framework
Available since 1.1
Return to top
Show: