ListView.SelectedListViewItemCollection 类
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
表示在列表视图控件中选定项的集合。
public: ref class ListView::SelectedListViewItemCollection : System::Collections::IList
public class ListView.SelectedListViewItemCollection : System.Collections.IList
[System.ComponentModel.ListBindable(false)]
public class ListView.SelectedListViewItemCollection : System.Collections.IList
type ListView.SelectedListViewItemCollection = class
interface IList
interface ICollection
interface IEnumerable
[<System.ComponentModel.ListBindable(false)>]
type ListView.SelectedListViewItemCollection = class
interface IList
interface ICollection
interface IEnumerable
Public Class ListView.SelectedListViewItemCollection
Implements IList
- 继承
-
ListView.SelectedListViewItemCollection
- 属性
- 实现
示例
下面的代码示例演示如何使用 SelectedItems、 SelectedIndexChanged 事件和 HeaderStyle 成员以及 ListView.SelectedListViewItemCollection 类。 若要运行此示例,请将以下代码粘贴到包含 ListView 名为 ListView1
的对象和 TextBox 名为 TextBox1
的 窗体中。
InitializeListView
从窗体的构造函数或Load事件处理程序调用 方法。 此示例要求事件处理程序与 事件正确关联SelectedIndexChanged
// This method adds two columns to the ListView, setting the Text
// and TextAlign, and Width properties of each ColumnHeader. The
// HeaderStyle property is set to NonClickable since the ColumnClick
// event is not handled. Finally the method adds ListViewItems and
// SubItems to each column.
void InitializeListView()
{
this->ListView1 = gcnew System::Windows::Forms::ListView;
this->ListView1->BackColor = System::Drawing::SystemColors::Control;
this->ListView1->Dock = System::Windows::Forms::DockStyle::Top;
this->ListView1->Location = System::Drawing::Point( 0, 0 );
this->ListView1->Name = "ListView1";
this->ListView1->Size = System::Drawing::Size( 292, 130 );
this->ListView1->TabIndex = 0;
this->ListView1->View = System::Windows::Forms::View::Details;
this->ListView1->MultiSelect = true;
this->ListView1->HideSelection = false;
this->ListView1->HeaderStyle = ColumnHeaderStyle::Nonclickable;
ColumnHeader^ columnHeader1 = gcnew ColumnHeader;
columnHeader1->Text = "Breakfast Item";
columnHeader1->TextAlign = HorizontalAlignment::Left;
columnHeader1->Width = 146;
ColumnHeader^ columnHeader2 = gcnew ColumnHeader;
columnHeader2->Text = "Price Each";
columnHeader2->TextAlign = HorizontalAlignment::Center;
columnHeader2->Width = 142;
this->ListView1->Columns->Add( columnHeader1 );
this->ListView1->Columns->Add( columnHeader2 );
array<String^>^foodList = {"Juice","Coffee","Cereal & Milk","Fruit Plate","Toast & Jelly","Bagel & Cream Cheese"};
array<String^>^foodPrice = {"1.09","1.09","2.19","2.49","1.49","1.49"};
for ( int count = 0; count < foodList->Length; count++ )
{
ListViewItem^ listItem = gcnew ListViewItem( foodList[ count ] );
listItem->SubItems->Add( foodPrice[ count ] );
ListView1->Items->Add( listItem );
}
this->Controls->Add( ListView1 );
}
// This method adds two columns to the ListView, setting the Text
// and TextAlign, and Width properties of each ColumnHeader. The
// HeaderStyle property is set to NonClickable since the ColumnClick
// event is not handled. Finally the method adds ListViewItems and
// SubItems to each column.
private void InitializeListView()
{
this.ListView1 = new System.Windows.Forms.ListView();
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.Name = "ListView1";
this.ListView1.Size = new System.Drawing.Size(292, 130);
this.ListView1.TabIndex = 0;
this.ListView1.View = System.Windows.Forms.View.Details;
this.ListView1.MultiSelect = true;
this.ListView1.HideSelection = false;
this.ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable;
ColumnHeader columnHeader1 = new ColumnHeader();
columnHeader1.Text = "Breakfast Item";
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",
"2.49", "1.49", "1.49"};
for(int count=0; count < foodList.Length; count++)
{
ListViewItem listItem = new ListViewItem(foodList[count]);
listItem.SubItems.Add(foodPrice[count]);
ListView1.Items.Add(listItem);
}
this.Controls.Add(ListView1);
}
' This method adds two columns to the ListView, setting the Text
' and TextAlign, and Width properties of each ColumnHeader. The
' HeaderStyle property is set to NonClickable since the ColumnClick
' event is not handled. Finally the method adds ListViewItems and
' SubItems to each column.
Private Sub InitializeListView()
Me.ListView1 = New System.Windows.Forms.ListView
Me.ListView1.BackColor = System.Drawing.SystemColors.Control
Me.ListView1.Dock = System.Windows.Forms.DockStyle.Top
Me.ListView1.Location = New System.Drawing.Point(0, 0)
Me.ListView1.Name = "ListView1"
Me.ListView1.Size = New System.Drawing.Size(292, 130)
Me.ListView1.TabIndex = 0
Me.ListView1.View = System.Windows.Forms.View.Details
Me.ListView1.MultiSelect = True
Me.ListView1.HideSelection = False
ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable
Dim columnHeader1 As New ColumnHeader
With columnHeader1
.Text = "Breakfast Item"
.TextAlign = HorizontalAlignment.Left
.Width = 146
End With
Dim columnHeader2 As New ColumnHeader
With columnHeader2
.Text = "Price Each"
.TextAlign = HorizontalAlignment.Center
.Width = 142
End With
Me.ListView1.Columns.Add(columnHeader1)
Me.ListView1.Columns.Add(columnHeader2)
Dim foodList() As String = New String() {"Juice", "Coffee", _
"Cereal & Milk", "Fruit Plate", "Toast & Jelly", _
"Bagel & Cream Cheese"}
Dim foodPrice() As String = New String() {"1.09", "1.09", _
"2.19", "2.49", "1.49", "1.49"}
Dim count As Integer
For count = 0 To foodList.Length - 1
Dim listItem As New ListViewItem(foodList(count))
listItem.SubItems.Add(foodPrice(count))
ListView1.Items.Add(listItem)
Next
Me.Controls.Add(Me.ListView1)
End Sub
// Uses the SelectedItems property to retrieve and tally the price
// of the selected menu items.
void ListView1_SelectedIndexChanged_UsingItems( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
ListView::SelectedListViewItemCollection^ breakfast = this->ListView1->SelectedItems;
double price = 0.0;
System::Collections::IEnumerator^ myEnum = breakfast->GetEnumerator();
while ( myEnum->MoveNext() )
{
ListViewItem^ item = safe_cast<ListViewItem^>(myEnum->Current);
price += Double::Parse( item->SubItems[ 1 ]->Text );
}
// Output the price to TextBox1.
TextBox1->Text = price.ToString();
}
// Uses the SelectedItems property to retrieve and tally the price
// of the selected menu items.
private void ListView1_SelectedIndexChanged_UsingItems(
object sender, System.EventArgs e)
{
ListView.SelectedListViewItemCollection breakfast =
this.ListView1.SelectedItems;
double price = 0.0;
foreach ( ListViewItem item in breakfast )
{
price += Double.Parse(item.SubItems[1].Text);
}
// Output the price to TextBox1.
TextBox1.Text = price.ToString();
}
' Uses the SelectedItems property to retrieve and tally the price
' of the selected menu items.
Private Sub ListView1_SelectedIndexChanged_UsingItems _
(ByVal sender As Object, ByVal e As System.EventArgs) _
Handles ListView1.SelectedIndexChanged
Dim breakfast As ListView.SelectedListViewItemCollection = _
Me.ListView1.SelectedItems
Dim item As ListViewItem
Dim price As Double = 0.0
For Each item In breakfast
price += Double.Parse(item.SubItems(1).Text)
Next
' Output the price to TextBox1.
TextBox1.Text = CType(price, String)
End Sub
注解
将 ListView.SelectedListViewItemCollection 所选项存储在 控件中 ListView 。 中存储的 ListView.SelectedListViewItemCollection 项是 中包含的 ListView.ListViewItemCollection项。 存储 ListView.ListViewItemCollection 中显示的 ListView所有项。
下表显示了 如何在 ListView.ListViewItemCollection 示例控件中存储 的 ListView 项及其选择状态的示例 ListView 。
索引 | Item | ListView 中的选择状态 |
---|---|---|
0 | Item1 | 未选定 |
1 | Item2 | 选定 |
2 | Item3 | 未选定 |
3 | Item4 | 选定 |
4 | Item5 | 选定 |
根据上 ListView.ListViewItemCollection 表中的示例,下表演示了 的显示方式 ListView.SelectedListViewItemCollection 。
索引 | ListViewItemCollection 中的选定项 |
---|---|
0 | Item2 |
1 | Item4 |
2 | Item5 |
可以使用此类的属性和方法对集合执行各种任务。 使用 Contains 方法可以确定 类中的 ListView.ListViewItemCollection 项是否为 的成员 ListView.SelectedListViewItemCollection。 知道项在集合中后,可以使用 IndexOf 方法确定项在 中 ListView.SelectedListViewItemCollection的位置。
构造函数
ListView.SelectedListViewItemCollection(ListView) |
初始化 ListView.SelectedListViewItemCollection 类的新实例。 |
属性
Count |
获取集合中的项数。 |
IsReadOnly |
获取一个值,该值指示集合是否为只读。 |
Item[Int32] |
获取集合中指定索引处的项。 |
Item[String] |
获取集合中具有指定键的项。 |
方法
Clear() |
从集合中移除所有项。 |
Contains(ListViewItem) |
确定指定项是否位于集合内。 |
ContainsKey(String) |
确定集合中是否包含具有指定键的项。 |
CopyTo(Array, Int32) |
将整个集合复制到现有数组中,从该数组内的指定位置开始复制。 |
Equals(Object) |
确定指定对象是否等于当前对象。 (继承自 Object) |
GetEnumerator() |
返回可用于循环访问选定项集合的枚举数。 |
GetHashCode() |
作为默认哈希函数。 (继承自 Object) |
GetType() |
获取当前实例的 Type。 (继承自 Object) |
IndexOf(ListViewItem) |
返回指定的项在集合中的索引。 |
IndexOfKey(String) |
返回具有指定键的项的第一个匹配项的索引。 |
MemberwiseClone() |
创建当前 Object 的浅表副本。 (继承自 Object) |
ToString() |
返回表示当前对象的字符串。 (继承自 Object) |
显式接口实现
ICollection.IsSynchronized |
获取一个值,该值指示对集合的访问是否为同步的(线程安全)。 |
ICollection.SyncRoot |
获取可用于同步控件集合访问的对象。 |
IList.Add(Object) |
向集合中添加一项。 |
IList.Contains(Object) |
确定指定项是否位于集合内。 |
IList.IndexOf(Object) |
返回指定的项在集合中的索引。 |
IList.Insert(Int32, Object) |
将某个项插入到集合中的指定索引处。 |
IList.IsFixedSize |
获取一个值,该值指示集合是否具有固定大小。 |
IList.Item[Int32] |
从集合中获取或设置对象。 |
IList.Remove(Object) |
从集合中移除指定项的第一个匹配项。 |
IList.RemoveAt(Int32) |
移除集合中指定索引处的项。 |
扩展方法
Cast<TResult>(IEnumerable) |
将 IEnumerable 的元素强制转换为指定的类型。 |
OfType<TResult>(IEnumerable) |
根据指定类型筛选 IEnumerable 的元素。 |
AsParallel(IEnumerable) |
启用查询的并行化。 |
AsQueryable(IEnumerable) |
将 IEnumerable 转换为 IQueryable。 |