TreeView.CheckedNodes 属性

参考

定义

命名空间:: System.Web.UI.WebControls

程序集:: System.Web.dll

重要

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获取 TreeNode 对象的集合，这些对象表示在 TreeView 控件中显示的选中了复选框的节点。

public:
 property System::Web::UI::WebControls::TreeNodeCollection ^ CheckedNodes { System::Web::UI::WebControls::TreeNodeCollection ^ get(); };

[System.ComponentModel.Browsable(false)]
public System.Web.UI.WebControls.TreeNodeCollection CheckedNodes { get; }

[<System.ComponentModel.Browsable(false)>]
member this.CheckedNodes : System.Web.UI.WebControls.TreeNodeCollection

Public ReadOnly Property CheckedNodes As TreeNodeCollection

属性值

TreeNodeCollection

一个 TreeNodeCollection，它包含 TreeView 中显示的选中了复选框的节点。

属性: BrowsableAttribute

示例

下面的代码示例演示如何使用 CheckedNodes 属性来确定哪些节点在控件中TreeView具有选定的检查框。


<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void Button_Click(Object sender, EventArgs e)
  {

    if(LinksTreeView.CheckedNodes.Count > 0)
    {

      // Clear the message label.
      Message.Text = "You selected: <br /><br />";

      // Iterate through the CheckedNodes collection and display the selected nodes.
      foreach (TreeNode node in LinksTreeView.CheckedNodes)
      {

        Message.Text += node.Text + "<br />";

      }

    }

    else
    {

      Message.Text = "No items selected.";

    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeView ShowCheckBoxes Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView ShowCheckBoxes Example</h3>
    
      <!-- Set the ShowCheckBoxes property declaratively.   -->
      <!-- Because the ShowCheckBoxes property uses a flag  -->
      <!-- enumeration, you can combine multiple values by  -->
      <!-- using the bitwise OR operator. In declarative    -->
      <!-- syntax, this is done using a comma separated     -->
      <!-- list.                                            -->
      <asp:TreeView id="LinksTreeView"
        Font-Names= "Arial"
        ForeColor="Blue"
        ExpandDepth="2"
        ShowCheckBoxes="Parent,Leaf" 
        runat="server">
         
        <LevelStyles>
        
          <asp:TreeNodeStyle ChildNodesPadding="10" 
            Font-Bold="true" 
            Font-Size="12pt" 
            ForeColor="DarkGreen"/>
          <asp:TreeNodeStyle ChildNodesPadding="5" 
            Font-Bold="true" 
            Font-Size="10pt"/>
          <asp:TreeNodeStyle ChildNodesPadding="5" 
            Font-UnderLine="true" 
            Font-Size="10pt"/>
          <asp:TreeNodeStyle ChildNodesPadding="10" 
            Font-Size="8pt"/>
             
        </LevelStyles>
         
        <Nodes>
        
          <asp:TreeNode Text="Table of Contents"
            SelectAction="None">
             
            <asp:TreeNode Text="Chapter One">
            
              <asp:TreeNode Text="Section 1.0">
              
                <asp:TreeNode Text="Topic 1.0.1"/>
                <asp:TreeNode Text="Topic 1.0.2"/>
                <asp:TreeNode Text="Topic 1.0.3"/>
              
              </asp:TreeNode>
              
              <asp:TreeNode Text="Section 1.1">
              
                <asp:TreeNode Text="Topic 1.1.1"/>
                <asp:TreeNode Text="Topic 1.1.2"/>
                <asp:TreeNode Text="Topic 1.1.3"/>
                <asp:TreeNode Text="Topic 1.1.4"/>
              
              </asp:TreeNode>
            
            </asp:TreeNode>
            
            <asp:TreeNode Text="Chapter Two">
            
              <asp:TreeNode Text="Section 2.0">
              
                <asp:TreeNode Text="Topic 2.0.1"/>
                <asp:TreeNode Text="Topic 2.0.2"/>
              
              </asp:TreeNode>
            
            </asp:TreeNode>
            
          </asp:TreeNode>
          <asp:TreeNode Text="Appendix A" />
          <asp:TreeNode Text="Appendix B" />
          <asp:TreeNode Text="Appendix C" />
        
        </Nodes>
        
      </asp:TreeView>
      
      <br /><br />
      
      <asp:Button id="Submit"
        Text="Select Items"
        OnClick="Button_Click"  
        runat="server"/>
         
      <br /><br />
      
      <asp:Label id="Message"
        runat="server"/>

    </form>
  </body>
</html>


<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Sub Button_Click(ByVal sender As Object, ByVal e As EventArgs)

    If LinksTreeView.CheckedNodes.Count > 0 Then

      ' Clear the message label.
      Message.Text = "You selected: <br /><br />"

      ' Iterate through the CheckedNodes collection and display the selected nodes.
      Dim node As TreeNode
      
      For Each node In LinksTreeView.CheckedNodes

        Message.Text &= node.Text & "<br />"

      Next

    Else

      Message.Text = "No items selected."

    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeView ShowCheckBoxes Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView ShowCheckBoxes Example</h3>
    
      <!-- Set the ShowCheckBoxes property declaratively.   -->
      <!-- Because the ShowCheckBoxes property uses a flag  -->
      <!-- enumeration, you can combine multiple values by  -->
      <!-- using the bitwise OR operator. In declarative    -->
      <!-- syntax, this is done using a comma separated     -->
      <!-- list.                                            -->
      <asp:TreeView id="LinksTreeView"
        Font-Names= "Arial"
        ForeColor="Blue"
        ExpandDepth="2"
        ShowCheckBoxes="Parent,Leaf" 
        runat="server">
         
        <LevelStyles>
        
          <asp:TreeNodeStyle ChildNodesPadding="10" 
            Font-Bold="true" 
            Font-Size="12pt" 
            ForeColor="DarkGreen"/>
          <asp:TreeNodeStyle ChildNodesPadding="5" 
            Font-Bold="true" 
            Font-Size="10pt"/>
          <asp:TreeNodeStyle ChildNodesPadding="5" 
            Font-UnderLine="true" 
            Font-Size="10pt"/>
          <asp:TreeNodeStyle ChildNodesPadding="10" 
            Font-Size="8pt"/>
             
        </LevelStyles>
         
        <Nodes>
        
          <asp:TreeNode Text="Table of Contents"
            SelectAction="None">
             
            <asp:TreeNode Text="Chapter One">
            
              <asp:TreeNode Text="Section 1.0">
              
                <asp:TreeNode Text="Topic 1.0.1"/>
                <asp:TreeNode Text="Topic 1.0.2"/>
                <asp:TreeNode Text="Topic 1.0.3"/>
              
              </asp:TreeNode>
              
              <asp:TreeNode Text="Section 1.1">
              
                <asp:TreeNode Text="Topic 1.1.1"/>
                <asp:TreeNode Text="Topic 1.1.2"/>
                <asp:TreeNode Text="Topic 1.1.3"/>
                <asp:TreeNode Text="Topic 1.1.4"/>
              
              </asp:TreeNode>
            
            </asp:TreeNode>
            
            <asp:TreeNode Text="Chapter Two">
            
              <asp:TreeNode Text="Section 2.0">
              
                <asp:TreeNode Text="Topic 2.0.1"/>
                <asp:TreeNode Text="Topic 2.0.2"/>
              
              </asp:TreeNode>
            
            </asp:TreeNode>
            
          </asp:TreeNode>
          <asp:TreeNode Text="Appendix A" />
          <asp:TreeNode Text="Appendix B" />
          <asp:TreeNode Text="Appendix C" />
        
        </Nodes>
        
      </asp:TreeView>
      
      <br /><br />
      
      <asp:Button id="Submit"
        Text="Select Items"
        OnClick="Button_Click"  
        runat="server"/>
         
      <br /><br />
      
      <asp:Label id="Message"
        runat="server"/>

    </form>
  </body>
</html>

注解

通过将属性设置为 ShowCheckBoxes) 以外的TreeNodeType.None值，在控件 (中TreeView显示检查框时，请使用 CheckedNodes 属性确定哪些节点显示所选检查框。此集合通常用于循环访问树中具有选定检查框的所有节点。

当TreeNodeCheckChanged控件的检查框TreeView在发帖到服务器之间更改状态时，将引发事件。这允许你提供一个事件处理方法，该方法在发生此事件时执行自定义例程，例如更新数据库或显示的内容。

注意

使用 CheckedNodes 树结构的深度优先遍历填充集合：在填充下一个父节点之前，每个父节点向下处理到其子节点。

适用于

TreeView.CheckedNodes 属性

定义

属性值

示例

注解

适用于

另请参阅

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