TreeNode.ImageIndex 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。
取得或設定樹狀節點處於未選取狀態時,顯示影像的影像清單索引值。
public:
property int ImageIndex { int get(); void set(int value); };
public int ImageIndex { get; set; }
[System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.TreeViewImageIndexConverter))]
[System.Windows.Forms.RelatedImageList("TreeView.ImageList")]
public int ImageIndex { get; set; }
member this.ImageIndex : int with get, set
[<System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.TreeViewImageIndexConverter))>]
[<System.Windows.Forms.RelatedImageList("TreeView.ImageList")>]
member this.ImageIndex : int with get, set
Public Property ImageIndex As Integer
屬性值
以零起始的索引值,表示指定 ImageList 中的影像位置。
- 屬性
例外狀況
.NET 5 和更新版本: value
小於 -2。
範例
下列程式碼範例會建立 並指派 ImageList 給 TreeView 控制項,並以 物件填入 TreeView 控制項 TreeNode 。 樹狀節點會從 指派的影像 ImageList ,當樹狀節點處於選取或未選取狀態時顯示。 這個範例需要您有 Form 包含 的 TreeView ,以及 ArrayList 包含每個包含 Customer
Order
物件的 物件。 它也需要 Customer
定義 和 Order
物件。
ref class Customer
{
public:
ArrayList^ CustomerOrders;
String^ CustomerName;
Customer( String^ myName )
{
CustomerName = myName;
CustomerOrders = gcnew ArrayList;
}
};
ref class Order
{
public:
String^ OrderID;
Order( String^ myOrderID )
{
this->OrderID = myOrderID;
}
};
void FillTreeView()
{
// Load the images in an ImageList.
ImageList^ myImageList = gcnew ImageList;
myImageList->Images->Add( Image::FromFile( "Default.gif" ) );
myImageList->Images->Add( Image::FromFile( "SelectedDefault.gif" ) );
myImageList->Images->Add( Image::FromFile( "Root.gif" ) );
myImageList->Images->Add( Image::FromFile( "UnselectedCustomer.gif" ) );
myImageList->Images->Add( Image::FromFile( "SelectedCustomer.gif" ) );
myImageList->Images->Add( Image::FromFile( "UnselectedOrder.gif" ) );
myImageList->Images->Add( Image::FromFile( "SelectedOrder.gif" ) );
// Assign the ImageList to the TreeView.
myTreeView->ImageList = myImageList;
// Set the TreeView control's default image and selected image indexes.
myTreeView->ImageIndex = 0;
myTreeView->SelectedImageIndex = 1;
/* Set the index of image from the
ImageList for selected and unselected tree nodes.*/
this->rootImageIndex = 2;
this->selectedCustomerImageIndex = 3;
this->unselectedCustomerImageIndex = 4;
this->selectedOrderImageIndex = 5;
this->unselectedOrderImageIndex = 6;
// Create the root tree node.
TreeNode^ rootNode = gcnew TreeNode( "CustomerList" );
rootNode->ImageIndex = rootImageIndex;
rootNode->SelectedImageIndex = rootImageIndex;
// Add a main root tree node.
myTreeView->Nodes->Add( rootNode );
// Add a root tree node for each Customer object in the ArrayList.
IEnumerator^ myEnum = customerArray->GetEnumerator();
while ( myEnum->MoveNext() )
{
Customer^ myCustomer = safe_cast<Customer^>(myEnum->Current);
// Add a child tree node for each Order object.
int countIndex = 0;
array<TreeNode^>^myTreeNodeArray = gcnew array<TreeNode^>(myCustomer->CustomerOrders->Count);
IEnumerator^ myEnum = myCustomer->CustomerOrders->GetEnumerator();
while ( myEnum->MoveNext() )
{
Order^ myOrder = safe_cast<Order^>(myEnum->Current);
// Add the Order tree node to the array.
myTreeNodeArray[ countIndex ] = gcnew TreeNode( myOrder->OrderID,unselectedOrderImageIndex,selectedOrderImageIndex );
countIndex++;
}
TreeNode^ customerNode = gcnew TreeNode( myCustomer->CustomerName,unselectedCustomerImageIndex,selectedCustomerImageIndex,myTreeNodeArray );
myTreeView->Nodes[ 0 ]->Nodes->Add( customerNode );
}
}
public class Customer
{
public ArrayList CustomerOrders;
public string CustomerName;
public Customer(string myName)
{
CustomerName = myName;
CustomerOrders = new ArrayList();
}
}
public class Order
{
public string OrderID;
public Order(string myOrderID )
{
this.OrderID = myOrderID;
}
}
private void FillTreeView()
{
// Load the images in an ImageList.
ImageList myImageList = new ImageList();
myImageList.Images.Add(Image.FromFile("Default.gif"));
myImageList.Images.Add(Image.FromFile("SelectedDefault.gif"));
myImageList.Images.Add(Image.FromFile("Root.gif"));
myImageList.Images.Add(Image.FromFile("UnselectedCustomer.gif"));
myImageList.Images.Add(Image.FromFile("SelectedCustomer.gif"));
myImageList.Images.Add(Image.FromFile("UnselectedOrder.gif"));
myImageList.Images.Add(Image.FromFile("SelectedOrder.gif"));
// Assign the ImageList to the TreeView.
myTreeView.ImageList = myImageList;
// Set the TreeView control's default image and selected image indexes.
myTreeView.ImageIndex = 0;
myTreeView.SelectedImageIndex = 1;
/* Set the index of image from the
ImageList for selected and unselected tree nodes.*/
this.rootImageIndex = 2;
this.selectedCustomerImageIndex = 3;
this.unselectedCustomerImageIndex = 4;
this.selectedOrderImageIndex = 5;
this.unselectedOrderImageIndex = 6;
// Create the root tree node.
TreeNode rootNode = new TreeNode("CustomerList");
rootNode.ImageIndex = rootImageIndex;
rootNode.SelectedImageIndex = rootImageIndex;
// Add a main root tree node.
myTreeView.Nodes.Add(rootNode);
// Add a root tree node for each Customer object in the ArrayList.
foreach(Customer myCustomer in customerArray)
{
// Add a child tree node for each Order object.
int countIndex=0;
TreeNode[] myTreeNodeArray = new TreeNode[myCustomer.CustomerOrders.Count];
foreach(Order myOrder in myCustomer.CustomerOrders)
{
// Add the Order tree node to the array.
myTreeNodeArray[countIndex] = new TreeNode(myOrder.OrderID,
unselectedOrderImageIndex, selectedOrderImageIndex);
countIndex++;
}
// Add the Customer tree node.
TreeNode customerNode = new TreeNode(myCustomer.CustomerName,
unselectedCustomerImageIndex, selectedCustomerImageIndex, myTreeNodeArray);
myTreeView.Nodes[0].Nodes.Add(customerNode);
}
}
Public Class Customer
Public CustomerOrders As ArrayList
Public CustomerName As String
Public Sub New(myName As String)
CustomerName = myName
CustomerOrders = New ArrayList()
End Sub
End Class
Public Class Order
Public OrderID As String
Public Sub New(myOrderID As String)
Me.OrderID = myOrderID
End Sub
End Class
Private Sub FillTreeView()
' Load the images in an ImageList.
Dim myImageList As New ImageList()
myImageList.Images.Add(Image.FromFile("Default.gif"))
myImageList.Images.Add(Image.FromFile("SelectedDefault.gif"))
myImageList.Images.Add(Image.FromFile("Root.gif"))
myImageList.Images.Add(Image.FromFile("UnselectedCustomer.gif"))
myImageList.Images.Add(Image.FromFile("SelectedCustomer.gif"))
myImageList.Images.Add(Image.FromFile("UnselectedOrder.gif"))
myImageList.Images.Add(Image.FromFile("SelectedOrder.gif"))
' Assign the ImageList to the TreeView.
myTreeView.ImageList = myImageList
' Set the TreeView control's default image and selected image indexes.
myTreeView.ImageIndex = 0
myTreeView.SelectedImageIndex = 1
' Set the index of image from the
' ImageList for selected and unselected tree nodes.
Me.rootImageIndex = 2
Me.selectedCustomerImageIndex = 3
Me.unselectedCustomerImageIndex = 4
Me.selectedOrderImageIndex = 5
Me.unselectedOrderImageIndex = 6
' Create the root tree node.
Dim rootNode As New TreeNode("CustomerList")
rootNode.ImageIndex = rootImageIndex
rootNode.SelectedImageIndex = rootImageIndex
' Add a main root tree node.
myTreeView.Nodes.Add(rootNode)
' Add a root tree node for each Customer object in the ArrayList.
Dim myCustomer As Customer
For Each myCustomer In customerArray
' Add a child tree node for each Order object.
Dim countIndex As Integer = 0
Dim myTreeNodeArray(myCustomer.CustomerOrders.Count) As TreeNode
Dim myOrder As Order
For Each myOrder In myCustomer.CustomerOrders
' Add the Order tree node to the array.
myTreeNodeArray(countIndex) = New TreeNode(myOrder.OrderID, _
unselectedOrderImageIndex, selectedOrderImageIndex)
countIndex += 1
Next myOrder
' Add the Customer tree node.
Dim customerNode As New TreeNode(myCustomer.CustomerName, _
unselectedCustomerImageIndex, selectedCustomerImageIndex, myTreeNodeArray)
myTreeView.Nodes(0).Nodes.Add(customerNode)
Next myCustomer
End Sub
備註
值 ImageIndex 是儲存在指派給 TreeView.ImageList 屬性之 ImageImageList 中的索引值。
注意
屬性的 ImageIndex 預設值與所指派控制項 TreeNode 的 TreeView 屬性相同 ImageIndex 。
ImageKey 和 ImageIndex 互斥,這表示如果設定其中一個,另一個會設定為不正確值並忽略。 如果您設定 ImageKey 屬性,屬性 ImageIndex 會自動設定為 -1。 或者,如果您設定 ImageIndex 屬性,會自動 ImageKey 將 設定為空字串 (「」) 。
.NET 5 和更新版本: 如果相關聯的 ImageList 屬性值變更為 null
,則 ImageIndex 屬性會傳回其預設值 -1。 不過,指派 ImageIndex 的值會在內部保留,並在另一個 ImageList 物件指派給 ImageList 屬性時使用。 如果指派給 ImageList 屬性的新 ImageList 具有 ImageList.ImageCollection.Count 小於或等於指派給 ImageIndex 屬性的值減一 (,以將集合視為以零起始的索引) , ImageIndex 屬性值會調整為小於屬性值的 Count 一個。
例如,假設有三個影像且屬性設定為 2 的 ImageIndex 按鈕控制項 ImageList 。 如果只有兩個影像的新 ImageList 指派給按鈕,則 ImageIndex 值會變更為 1。