ListView.Groups 屬性
定義
重要
部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。
取得指派給控制項的 ListViewGroup 物件集合。
public:
property System::Windows::Forms::ListViewGroupCollection ^ Groups { System::Windows::Forms::ListViewGroupCollection ^ get(); };public System.Windows.Forms.ListViewGroupCollection Groups { get; }member this.Groups : System.Windows.Forms.ListViewGroupCollectionPublic ReadOnly Property Groups As ListViewGroupCollection屬性值
ListViewGroupCollection，其中包含 ListView 控制項中的所有群組。
範例
下列程式碼範例示範如何使用 ListView 群組功能，依詳細資料檢視中的子專案值來組織專案。 這種群組形式類似于 Windows 檔案總管中使用的群組。 在此範例中，會動態建立群組。 針對每個子專案資料行，會為每個唯一子專案值建立一個群組。 針對父專案資料行，會為每個唯一的初始字母建立一個群組。 按一下資料行的標頭會將專案排序為針對該資料行建立的群組。 再次按一下相同的資料行標頭會反轉群組的順序。
#using <mscorlib.dll>
#using <System.Drawing.dll>
#using <System.dll>
#using <System.Windows.Forms.dll>
using namespace System;
using namespace System::Collections;
using namespace System::Windows::Forms;
public ref class ListViewGroupsExample : public Form
{
private:
ListView^ myListView;
bool isRunningXPOrLater;
// Declare a Hashtable array in which to store the groups.
array<Hashtable^>^ groupTables;
// Declare a variable to store the current grouping column.
int groupColumn;
public:
ListViewGroupsExample()
{
groupColumn = 0;
// Initialize myListView.
myListView = gcnew ListView();
myListView->Dock = DockStyle::Fill;
myListView->View = View::Details;
myListView->Sorting = SortOrder::Ascending;
// Create and initialize column headers for myListView.
ColumnHeader^ columnHeader0 = gcnew ColumnHeader();
columnHeader0->Text = "Title";
columnHeader0->Width = -1;
ColumnHeader^ columnHeader1 = gcnew ColumnHeader();
columnHeader1->Text = "Author";
columnHeader1->Width = -1;
ColumnHeader^ columnHeader2 = gcnew ColumnHeader();
columnHeader2->Text = "Year";
columnHeader2->Width = -1;
// Add the column headers to myListView.
array<ColumnHeader^>^ temp0 = {columnHeader0, columnHeader1, columnHeader2};
myListView->Columns->AddRange(temp0);
// Add a handler for the ColumnClick event.
myListView->ColumnClick +=
gcnew ColumnClickEventHandler(this, &ListViewGroupsExample::myListView_ColumnClick);
// Create items and add them to myListView.
array<String^>^ temp1 = {"Programming Windows", "Petzold, Charles", "1998"};
ListViewItem^ item0 = gcnew ListViewItem( temp1 );
array<String^>^ temp2 = {"Code: The Hidden Language of Computer Hardware and Software",
"Petzold, Charles", "2000"};
ListViewItem^ item1 = gcnew ListViewItem( temp2 );
array<String^>^ temp3 = {"Programming Windows with C#", "Petzold, Charles", "2001"};
ListViewItem^ item2 = gcnew ListViewItem( temp3 );
array<String^>^ temp4 = {"Coding Techniques for Microsoft Visual Basic .NET",
"Connell, John", "2001"};
ListViewItem^ item3 = gcnew ListViewItem( temp4 );
array<String^>^ temp5 = {"C# for Java Developers", "Jones, Allen & Freeman, Adam",
"2002"};
ListViewItem^ item4 = gcnew ListViewItem( temp5 );
array<String^>^ temp6 = {"Microsoft .NET XML Web Services Step by Step",
"Jones, Allen & Freeman, Adam", "2002"};
ListViewItem^ item5 = gcnew ListViewItem( temp6 );
array<ListViewItem^>^ temp7 = {item0, item1, item2, item3, item4, item5};
myListView->Items->AddRange( temp7 );
// Determine whether Windows XP or a later
// operating system is present.
isRunningXPOrLater = false;
if (System::Environment::OSVersion->Version->Major > 5 ||
( System::Environment::OSVersion->Version->Major == 5 &&
System::Environment::OSVersion->Version->Minor >= 1) )
{
isRunningXPOrLater = true;
}
if (isRunningXPOrLater)
{
// Create the groupsTable array and populate it with one
// hash table for each column.
groupTables = gcnew array<Hashtable^>(myListView->Columns->Count);
for (int column = 0; column < myListView->Columns->Count; column++)
{
// Create a hash table containing all the groups
// needed for a single column.
groupTables[column] = CreateGroupsTable(column);
}
// Start with the groups created for the Title column.
SetGroups(0);
}
// Initialize the form.
this->Controls->Add(myListView);
this->Size = System::Drawing::Size(550, 330);
this->Text = "ListView Groups Example";
}
// Groups the items using the groups created for the clicked
// column.
private:
void myListView_ColumnClick(
Object^ /*sender*/, ColumnClickEventArgs^ e)
{
// Set the sort order to ascending when changing
// column groups; otherwise, reverse the sort order.
if ( myListView->Sorting == SortOrder::Descending ||
( isRunningXPOrLater && (e->Column != groupColumn) ) )
{
myListView->Sorting = SortOrder::Ascending;
}
else
{
myListView->Sorting = SortOrder::Descending;
}
groupColumn = e->Column;
// Set the groups to those created for the clicked column.
if (isRunningXPOrLater)
{
SetGroups(e->Column);
}
}
// Sets myListView to the groups created for the specified column.
private:
void SetGroups(int column)
{
// Remove the current groups.
myListView->Groups->Clear();
// Retrieve the hash table corresponding to the column.
Hashtable^ groups = dynamic_cast<Hashtable^>(groupTables[column]);
// Copy the groups for the column to an array.
array<ListViewGroup^>^ groupsArray = gcnew array<ListViewGroup^>(groups->Count);
groups->Values->CopyTo(groupsArray, 0);
// Sort the groups and add them to myListView.
Array::Sort(groupsArray, gcnew ListViewGroupSorter(myListView->Sorting));
myListView->Groups->AddRange(groupsArray);
// Iterate through the items in myListView, assigning each
// one to the appropriate group.
IEnumerator^ myEnum = myListView->Items->GetEnumerator();
while (myEnum->MoveNext())
{
ListViewItem^ item = safe_cast<ListViewItem^>(myEnum->Current);
// Retrieve the subitem text corresponding to the column.
String^ subItemText = item->SubItems[column]->Text;
// For the Title column, use only the first letter.
if (column == 0)
{
subItemText = subItemText->Substring(0, 1);
}
// Assign the item to the matching group.
item->Group = dynamic_cast<ListViewGroup^>(groups[subItemText]);
}
}
// Creates a Hashtable object with one entry for each unique
// subitem value (or initial letter for the parent item)
// in the specified column.
private:
Hashtable^ CreateGroupsTable(int column)
{
// Create a Hashtable object.
Hashtable^ groups = gcnew Hashtable();
// Iterate through the items in myListView.
IEnumerator^ myEnum1 = myListView->Items->GetEnumerator();
while (myEnum1->MoveNext())
{
ListViewItem^ item = safe_cast<ListViewItem^>(myEnum1->Current);
// Retrieve the text value for the column.
String^ subItemText = item->SubItems[column]->Text;
// Use the initial letter instead if it is the first column.
if (column == 0)
{
subItemText = subItemText->Substring(0, 1);
}
// If the groups table does not already contain a group
// for the subItemText value, add a new group using the
// subItemText value for the group header and Hashtable key.
if (!groups->Contains(subItemText))
{
groups->Add( subItemText, gcnew ListViewGroup(subItemText,
HorizontalAlignment::Left) );
}
}
// Return the Hashtable object.
return groups;
}
// Sorts ListViewGroup objects by header value.
ref class ListViewGroupSorter : public IComparer
{
private:
SortOrder order;
// Stores the sort order.
public:
ListViewGroupSorter(SortOrder theOrder)
{
order = theOrder;
}
// Compares the groups by header value, using the saved sort
// order to return the correct value.
virtual int Compare(Object^ x, Object^ y)
{
int result = String::Compare(
(dynamic_cast<ListViewGroup^>(x))->Header,
(dynamic_cast<ListViewGroup^>(y))->Header
);
if (order == SortOrder::Ascending)
{
return result;
}
else
{
return -result;
}
}
};
};
[STAThread]
int main()
{
Application::EnableVisualStyles();
Application::Run(gcnew ListViewGroupsExample());
}
using System;
using System.Collections;
using System.Windows.Forms;
public class ListViewGroupsExample : Form
{
private ListView myListView;
// Determine whether Windows XP or a later
// operating system is present.
private bool isRunningXPOrLater =
OSFeature.Feature.IsPresent(OSFeature.Themes);
// Declare a Hashtable array in which to store the groups.
private Hashtable[] groupTables;
// Declare a variable to store the current grouping column.
int groupColumn = 0;
public ListViewGroupsExample()
{
// Initialize myListView.
myListView = new ListView();
myListView.Dock = DockStyle.Fill;
myListView.View = View.Details;
myListView.Sorting = SortOrder.Ascending;
// Create and initialize column headers for myListView.
ColumnHeader columnHeader0 = new ColumnHeader();
columnHeader0.Text = "Title";
columnHeader0.Width = -1;
ColumnHeader columnHeader1 = new ColumnHeader();
columnHeader1.Text = "Author";
columnHeader1.Width = -1;
ColumnHeader columnHeader2 = new ColumnHeader();
columnHeader2.Text = "Year";
columnHeader2.Width = -1;
// Add the column headers to myListView.
myListView.Columns.AddRange(new ColumnHeader[]
{columnHeader0, columnHeader1, columnHeader2});
// Add a handler for the ColumnClick event.
myListView.ColumnClick +=
new ColumnClickEventHandler(myListView_ColumnClick);
// Create items and add them to myListView.
ListViewItem item0 = new ListViewItem( new string[]
{"Programming Windows",
"Petzold, Charles",
"1998"} );
ListViewItem item1 = new ListViewItem( new string[]
{"Code: The Hidden Language of Computer Hardware and Software",
"Petzold, Charles",
"2000"} );
ListViewItem item2 = new ListViewItem( new string[]
{"Programming Windows with C#",
"Petzold, Charles",
"2001"} );
ListViewItem item3 = new ListViewItem( new string[]
{"Coding Techniques for Microsoft Visual Basic .NET",
"Connell, John",
"2001"} );
ListViewItem item4 = new ListViewItem( new string[]
{"C# for Java Developers",
"Jones, Allen & Freeman, Adam",
"2002"} );
ListViewItem item5 = new ListViewItem( new string[]
{"Microsoft .NET XML Web Services Step by Step",
"Jones, Allen & Freeman, Adam",
"2002"} );
myListView.Items.AddRange(
new ListViewItem[] {item0, item1, item2, item3, item4, item5});
if (isRunningXPOrLater)
{
// Create the groupsTable array and populate it with one
// hash table for each column.
groupTables = new Hashtable[myListView.Columns.Count];
for (int column = 0; column < myListView.Columns.Count; column++)
{
// Create a hash table containing all the groups
// needed for a single column.
groupTables[column] = CreateGroupsTable(column);
}
// Start with the groups created for the Title column.
SetGroups(0);
}
// Initialize the form.
this.Controls.Add(myListView);
this.Size = new System.Drawing.Size(550, 330);
this.Text = "ListView Groups Example";
}
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.Run(new ListViewGroupsExample());
}
// Groups the items using the groups created for the clicked
// column.
private void myListView_ColumnClick(
object sender, ColumnClickEventArgs e)
{
// Set the sort order to ascending when changing
// column groups; otherwise, reverse the sort order.
if ( myListView.Sorting == SortOrder.Descending ||
( isRunningXPOrLater && (e.Column != groupColumn) ) )
{
myListView.Sorting = SortOrder.Ascending;
}
else
{
myListView.Sorting = SortOrder.Descending;
}
groupColumn = e.Column;
// Set the groups to those created for the clicked column.
if (isRunningXPOrLater)
{
SetGroups(e.Column);
}
}
// Sets myListView to the groups created for the specified column.
private void SetGroups(int column)
{
// Remove the current groups.
myListView.Groups.Clear();
// Retrieve the hash table corresponding to the column.
Hashtable groups = (Hashtable)groupTables[column];
// Copy the groups for the column to an array.
ListViewGroup[] groupsArray = new ListViewGroup[groups.Count];
groups.Values.CopyTo(groupsArray, 0);
// Sort the groups and add them to myListView.
Array.Sort(groupsArray, new ListViewGroupSorter(myListView.Sorting));
myListView.Groups.AddRange(groupsArray);
// Iterate through the items in myListView, assigning each
// one to the appropriate group.
foreach (ListViewItem item in myListView.Items)
{
// Retrieve the subitem text corresponding to the column.
string subItemText = item.SubItems[column].Text;
// For the Title column, use only the first letter.
if (column == 0)
{
subItemText = subItemText.Substring(0, 1);
}
// Assign the item to the matching group.
item.Group = (ListViewGroup)groups[subItemText];
}
}
// Creates a Hashtable object with one entry for each unique
// subitem value (or initial letter for the parent item)
// in the specified column.
private Hashtable CreateGroupsTable(int column)
{
// Create a Hashtable object.
Hashtable groups = new Hashtable();
// Iterate through the items in myListView.
foreach (ListViewItem item in myListView.Items)
{
// Retrieve the text value for the column.
string subItemText = item.SubItems[column].Text;
// Use the initial letter instead if it is the first column.
if (column == 0)
{
subItemText = subItemText.Substring(0, 1);
}
// If the groups table does not already contain a group
// for the subItemText value, add a new group using the
// subItemText value for the group header and Hashtable key.
if (!groups.Contains(subItemText))
{
groups.Add( subItemText, new ListViewGroup(subItemText,
HorizontalAlignment.Left) );
}
}
// Return the Hashtable object.
return groups;
}
// Sorts ListViewGroup objects by header value.
private class ListViewGroupSorter : IComparer
{
private SortOrder order;
// Stores the sort order.
public ListViewGroupSorter(SortOrder theOrder)
{
order = theOrder;
}
// Compares the groups by header value, using the saved sort
// order to return the correct value.
public int Compare(object x, object y)
{
int result = String.Compare(
((ListViewGroup)x).Header,
((ListViewGroup)y).Header
);
if (order == SortOrder.Ascending)
{
return result;
}
else
{
return -result;
}
}
}
}
Imports System.Collections
Imports System.Windows.Forms
Public Class ListViewGroupsExample
Inherits Form
Private myListView As ListView
' Determine whether Windows XP or a later
' operating system is present.
Private isRunningXPOrLater As Boolean = _
OSFeature.Feature.IsPresent(OSFeature.Themes)
' Declare a Hashtable array in which to store the groups.
Private groupTables() As Hashtable
' Declare a variable to store the current grouping column.
Private groupColumn As Integer = 0
Public Sub New()
' Initialize myListView.
myListView = New ListView()
myListView.Dock = DockStyle.Fill
myListView.View = View.Details
myListView.Sorting = SortOrder.Ascending
' Create and initialize column headers for myListView.
Dim columnHeader0 As New ColumnHeader()
columnHeader0.Text = "Title"
columnHeader0.Width = -1
Dim columnHeader1 As New ColumnHeader()
columnHeader1.Text = "Author"
columnHeader1.Width = -1
Dim columnHeader2 As New ColumnHeader()
columnHeader2.Text = "Year"
columnHeader2.Width = -1
' Add the column headers to myListView.
myListView.Columns.AddRange( New ColumnHeader() _
{columnHeader0, columnHeader1, columnHeader2} )
' Add a handler for the ColumnClick event.
AddHandler myListView.ColumnClick, AddressOf myListView_ColumnClick
' Create items and add them to myListView.
Dim item0 As New ListViewItem( New String() _
{"Programming Windows", _
"Petzold, Charles", _
"1998"} )
Dim item1 As New ListViewItem( New String() _
{"Code: The Hidden Language of Computer Hardware and Software", _
"Petzold, Charles", _
"2000"} )
Dim item2 As New ListViewItem( New String() _
{"Programming Windows with C#", _
"Petzold, Charles", _
"2001"} )
Dim item3 As New ListViewItem( New String() _
{"Coding Techniques for Microsoft Visual Basic .NET", _
"Connell, John", _
"2001"} )
Dim item4 As New ListViewItem( New String() _
{"C# for Java Developers", _
"Jones, Allen / Freeman, Adam", _
"2002"} )
Dim item5 As New ListViewItem( New String() _
{"Microsoft .NET XML Web Services Step by Step", _
"Jones, Allen / Freeman, Adam", _
"2002"} )
myListView.Items.AddRange( _
New ListViewItem() {item0, item1, item2, item3, item4, item5})
If isRunningXPOrLater
' Create the groupsTable array and populate it with one
' hash table for each column.
groupTables = New Hashtable(myListView.Columns.Count) {}
Dim column As Integer
For column = 0 To myListView.Columns.Count - 1
' Create a hash table containing all the groups
' needed for a single column.
groupTables(column) = CreateGroupsTable(column)
Next column
' Start with the groups created for the Title column.
SetGroups(0)
End If
' Initialize the form.
Me.Controls.Add(myListView)
Me.Size = New System.Drawing.Size(550, 330)
Me.Text = "ListView Groups Example"
End Sub
<STAThread()> _
Shared Sub Main()
Application.EnableVisualStyles()
Application.Run(New ListViewGroupsExample())
End Sub
' Groups the items using the groups created for the clicked
' column.
Private Sub myListView_ColumnClick( _
sender As Object, e As ColumnClickEventArgs)
' Set the sort order to ascending when changing
' column groups; otherwise, reverse the sort order.
If myListView.Sorting = SortOrder.Descending OrElse _
isRunningXPOrLater And e.Column <> groupColumn Then
myListView.Sorting = SortOrder.Ascending
Else
myListView.Sorting = SortOrder.Descending
End If
groupColumn = e.Column
' Set the groups to those created for the clicked column.
If isRunningXPOrLater Then
SetGroups(e.Column)
End If
End Sub
' Sets myListView to the groups created for the specified column.
Private Sub SetGroups(column As Integer)
' Remove the current groups.
myListView.Groups.Clear()
' Retrieve the hash table corresponding to the column.
Dim groups As Hashtable = CType(groupTables(column), Hashtable)
' Copy the groups for the column to an array.
Dim groupsArray(groups.Count - 1) As ListViewGroup
groups.Values.CopyTo(groupsArray, 0)
' Sort the groups and add them to myListView.
Array.Sort(groupsArray, New ListViewGroupSorter(myListView.Sorting))
myListView.Groups.AddRange(groupsArray)
' Iterate through the items in myListView, assigning each
' one to the appropriate group.
Dim item As ListViewItem
For Each item In myListView.Items
' Retrieve the subitem text corresponding to the column.
Dim subItemText As String = item.SubItems(column).Text
' For the Title column, use only the first letter.
If column = 0 Then
subItemText = subItemText.Substring(0, 1)
End If
' Assign the item to the matching group.
item.Group = CType(groups(subItemText), ListViewGroup)
Next item
End Sub
' Creates a Hashtable object with one entry for each unique
' subitem value (or initial letter for the parent item)
' in the specified column.
Private Function CreateGroupsTable(column As Integer) As Hashtable
' Create a Hashtable object.
Dim groups As New Hashtable()
' Iterate through the items in myListView.
Dim item As ListViewItem
For Each item In myListView.Items
' Retrieve the text value for the column.
Dim subItemText As String = item.SubItems(column).Text
' Use the initial letter instead if it is the first column.
If column = 0 Then
subItemText = subItemText.Substring(0, 1)
End If
' If the groups table does not already contain a group
' for the subItemText value, add a new group using the
' subItemText value for the group header and Hashtable key.
If Not groups.Contains(subItemText) Then
groups.Add( subItemText, New ListViewGroup(subItemText, _
HorizontalAlignment.Left) )
End If
Next item
' Return the Hashtable object.
Return groups
End Function 'CreateGroupsTable
' Sorts ListViewGroup objects by header value.
Private Class ListViewGroupSorter
Implements IComparer
Private order As SortOrder
' Stores the sort order.
Public Sub New(theOrder As SortOrder)
order = theOrder
End Sub
' Compares the groups by header value, using the saved sort
' order to return the correct value.
Public Function Compare(x As Object, y As Object) As Integer _
Implements IComparer.Compare
Dim result As Integer = String.Compare( _
CType(x, ListViewGroup).Header, _
CType(y, ListViewGroup).Header )
If order = SortOrder.Ascending Then
Return result
Else
Return -result
End If
End Function 'Compare
End Class
End Class
備註
群組 ListView 功能可讓您建立邏輯相關 ListView 專案的視覺群組。 每個群組都包含文字標頭，後面接著水平線和指派給該群組的專案。 您可以將標題文字對齊控制項的左、右或中央。 每當屬性設定為 以外的 View.List 值時， View 就會顯示指派給 ListView 控制項的任何群組。
ListView 群組可協助使用者藉由將專案分成有用的類別，來尋找他們所尋找的專案。 您可以建立您需要的任何類別。 其中一個典型的方法是根據清單的排序方式來分組專案。 例如，當清單依字母順序排序，或是依子專案排序時，您可以依專案名稱的初始字母來分組專案，例如在詳細資料檢視中按一下資料行標頭來排序清單時，例如類型或日期。 Windows 檔案總管會使用這種類型的群組。
若要使用群組功能，請將一或多個 ListViewGroup 物件新增至 Groups 控制項的 ListView 集合。 在建構函式中 ListViewGroup 設定群組標頭文字和標頭對齊方式，或使用 和 ListViewGroup.HeaderAlignment 屬性加以設定 ListViewGroup.Header 。
若要暫時停用群組功能，請將 ShowGroups 屬性設定為 false 。
您可以藉由在建構函式中 ListViewItem 指定群組、設定 ListViewItem.Group 屬性，或直接將專案新增至群組的集合，將專案指派給 ListViewGroup.Items 群組。 所有專案都應該在顯示之前指派給群組。 未指派給群組的任何專案都會出現在預設群組中，其標題標籤為 「DefaultGroup {0} 」。 預設群組不包含在集合中 Groups ，而且無法改變。 它主要用於偵錯，以確保所有專案都已正確新增至群組。
專案一次只能位於一個群組中。 您可以在執行時間設定 ListViewItem.Group 屬性，或將它新增至 ListViewGroup.Items 另一個群組的集合，以變更專案所屬的群組，以自動從上一個群組中移除它。
使用群組時，會停用插入標記功能。 這是因為群組功能會依群組成員資格排序專案，而插入標記功能則用於控制項中 ListView 尚未排序其專案的拖放重新置放。
ListView 當您的應用程式呼叫 Application.EnableVisualStyles 方法時，只能在 Windows XP 和 Windows Server 2003 上使用群組。 在先前的作業系統上，與群組相關的任何程式碼都不會有任何作用，而且群組不會出現。 因此，相依于群組功能的任何程式碼可能無法正常運作。
您可能想要包含可判斷群組功能是否可用的程式碼，並在無法使用時提供替代功能。 例如，您可能想要在不支援依群組排序的作業系統上執行時，提供替代排序。
群組功能是由提供作業系統主題功能的相同程式庫所提供。 若要檢查此程式庫的可用性，請呼叫 FeatureSupport.IsPresent(Object) 方法多載並傳入 OSFeature.Themes 值。
