ItemCheckEventArgs 類別

定義

命名空間:

System.Windows.Forms

組件:

System.Windows.Forms.dll

來源:

ItemCheckEventArgs.cs

提供 ItemCheck 和 CheckedListBox 控制項的 ListView 事件資料。

C#

public class ItemCheckEventArgs : EventArgs

繼承

Object

EventArgs

ItemCheckEventArgs

範例

下列程式碼範例示範處理 ListView.ItemCheck 事件的核取 ListView 控制項。 方法會使用 CurrentValue 物件的 和 Index 屬性 ItemCheckEventArgs ，來擷取並計算所選取功能表項目的價格。 若要執行此範例，請將下列程式碼貼到包含 ListView 具名 ListView1 和 TextBox 具名 Textbox1 的表單中。 InitializeListView從表單的建構函式或 Load 方法呼叫 方法。 確定所有事件都與其事件處理方法相關聯。

C#

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);
}

C#

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();
}

備註

當 ItemCheck 核取清單方塊中專案的核取狀態變更時，就會發生此事件。 類別 ItemCheckEventArgs 會指定要變更之專案的索引、專案的目前核取方塊值，以及要為核取方塊設定的新值。

如需處理事件的詳細資訊，請參閱 處理和引發事件。

建構函式

ItemCheckEventArgs(Int32, CheckState, CheckState)

初始化 ItemCheckEventArgs 類別的新執行個體。

屬性

CurrentValue	取得值，指出項目的核取方塊目前的狀態。
Index	取得要變更項目之以零為起始的索引。
NewValue	取得或設定值，指出項目的核取方塊要設定為已核取、未核取或是不定。

適用於

另請參閱

• CheckedListBox
• ItemCheck