TreeNode.ValuePath 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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获取从根节点到当前节点的路径。

public:
 property System::String ^ ValuePath { System::String ^ get(); };

[System.ComponentModel.Browsable(false)]
public string ValuePath { get; }

[<System.ComponentModel.Browsable(false)>]
member this.ValuePath : string

Public ReadOnly Property ValuePath As String

属性值

String

由分隔符分隔的节点值列表，这些值构成从根节点到当前节点的路径。

属性: BrowsableAttribute

示例

下面的代码示例演示如何分析 ValuePath 属性。


<%@ 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 Index_Changed(Object sender, EventArgs e)
  {

    // Set the PathSeparator character based on the user's selection.
    // Notice that the value must be converted to a Char data type.
    BookTreeView.PathSeparator = Convert.ToChar(List.SelectedItem.Text);

    // Display the ValuePath values for the second-level nodes.
    Message.Text = "The ValuePath values for the second-level nodes are:<br />";
    foreach(TreeNode node in BookTreeView.Nodes[0].ChildNodes)
    {

      // Create the delimiter array with the PathSeparator value for the Split method.
      Char[] DelimiterArray = new Char[1];
      DelimiterArray[0] = BookTreeView.PathSeparator;

      // Parse the ValuePath value using the delimiter array.
      String[] NodeValues = node.ValuePath.Split(DelimiterArray);

      // Display the node values.
      for(int i=0; i<NodeValues.Length; i++)
      {
        if(i != NodeValues.Length - 1)
        {   
          // Append the delimiter character.
          Message.Text += NodeValues[i] + BookTreeView.PathSeparator.ToString();
        }
        else
        {
          // Do not append the delimiter character.
          Message.Text += NodeValues[i];
        }

      }

      // Append a line break for the next node.
      Message.Text += "<br />";

    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >

  <head runat="server">
    <title>TreeView PathSeparator Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView PathSeparator Example</h3>
      
      <asp:TreeView id="BookTreeView"
        ExpandDepth="-1"
        PathSeparator="/"
        runat="server">
         
        <Nodes>
        
          <asp:TreeNode Value="Chapter 1" 
            Text="Chapter 1">
             
            <asp:TreeNode Value="Section 1"
              Text="Section 1">
               
              <asp:TreeNode Value="Paragraph 1" 
                Text="Paragraph 1">
              </asp:TreeNode>
                
            </asp:TreeNode>
            
            <asp:TreeNode Value="Section 2" 
              Text="Section 2">
            </asp:TreeNode>
            
          </asp:TreeNode>
        
        </Nodes>
        
      </asp:TreeView>
      
      <br />
      
      <asp:Label id="Message" runat="server"/>
      
      <hr />
      
      Select a path separator value:<br />
      
      <asp:DropDownList ID="List"
        AutoPostBack="true"
        OnSelectedIndexChanged="Index_Changed"   
        runat="server">
      
        <asp:ListItem Selected="true">/</asp:ListItem>
        <asp:ListItem>\</asp:ListItem>
        <asp:ListItem>|</asp:ListItem>
        <asp:ListItem>,</asp:ListItem>
        <asp:ListItem>;</asp:ListItem>
      
      </asp:DropDownList>

    </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 Index_Changed(ByVal sender As Object, ByVal e As EventArgs)

    ' Set the PathSeparator character based on the user's selection.
    ' Notice that the value must be converted to a Char data type.
    BookTreeView.PathSeparator = Convert.ToChar(List.SelectedItem.Text)

    ' Display the ValuePath values for the second-level nodes.
    Message.Text = "The ValuePath values for the second-level nodes are:<br />"
    Dim node As TreeNode
    For Each node In BookTreeView.Nodes(0).ChildNodes

      ' Create the delimiter array with the PathSeparator value for the Split method.
      Dim DelimiterArray(1) As Char
      DelimiterArray(0) = BookTreeView.PathSeparator

      ' Parse the ValuePath value using the delimiter array.
      Dim NodeValues() As String = node.ValuePath.Split(DelimiterArray)

      ' Display the node values.
      Dim i As Integer

      For i = 0 To NodeValues.Length - 1

        If i <> NodeValues.Length - 1 Then

          ' Append the delimiter character.
          Message.Text &= NodeValues(i) & BookTreeView.PathSeparator.ToString()

        Else

          ' Do not append the delimiter character.
          Message.Text &= NodeValues(i)

        End If

      Next

      ' Append a line break for the next node.
      Message.Text &= "<br />"

    Next

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >

  <head runat="server">
    <title>TreeView PathSeparator Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeView PathSeparator Example</h3>
      
      <asp:TreeView id="BookTreeView"
        ExpandDepth="-1"
        PathSeparator="/"
        runat="server">
         
        <Nodes>
        
          <asp:TreeNode Value="Chapter 1" 
            Text="Chapter 1">
             
            <asp:TreeNode Value="Section 1"
              Text="Section 1">
               
              <asp:TreeNode Value="Paragraph 1" 
                Text="Paragraph 1">
              </asp:TreeNode>
                
            </asp:TreeNode>
            
            <asp:TreeNode Value="Section 2" 
              Text="Section 2">
            </asp:TreeNode>
            
          </asp:TreeNode>
        
        </Nodes>
        
      </asp:TreeView>
      
      <br />
      
      <asp:Label id="Message" runat="server"/>
      
      <hr />
      
      Select a path separator value:<br />
      
      <asp:DropDownList ID="List"
        AutoPostBack="true"
        OnSelectedIndexChanged="Index_Changed"   
        runat="server">
      
        <asp:ListItem Selected="true">/</asp:ListItem>
        <asp:ListItem>\</asp:ListItem>
        <asp:ListItem>|</asp:ListItem>
        <asp:ListItem>,</asp:ListItem>
        <asp:ListItem>;</asp:ListItem>
      
      </asp:DropDownList>

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

注解

属性 ValuePath 包含以分隔符分隔的节点值列表，这些节点值构成从根节点到当前节点的路径。 PathSeparator使用属性指定用于分隔节点值的分隔符字符。此值通常在分析单个值的列表时使用，或作为参数传递给 FindNode 类的 TreeView 方法。

根据控件中显示的 TreeView 值，可能需要更改分隔符字符以防止任何冲突。例如，如果将分隔符字符设置为逗号，则显示的值不应包含任何逗号;否则，无法准确分析 ValuePath 属性。

注意

同一级别的节点必须具有属性的唯一值 Value ; TreeView 控件无法区分同一级别具有相同值的不同节点。在此方案中，如果用户单击具有重复值的节点，则会选择控件中 TreeView 第一个显示的节点。

适用于

TreeNode.ValuePath 属性

定义

属性值

示例

注解

适用于

另请参阅

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