TreeNode Constructors

Definition

Initializes a new instance of the TreeNode class.

Overloads

TreeNode()

Initializes a new instance of the TreeNode class without text or a value.

TreeNode(String)

Initializes a new instance of the TreeNode class using the specified text.

TreeNode(String, String)

Initializes a new instance of the TreeNode class using the specified text and value.

TreeNode(TreeView, Boolean)

Initializes a new instance of the TreeNode class using the specified owner.

TreeNode(String, String, String)

Initializes a new instance of the TreeNode class using the specified text, value, and image URL.

TreeNode(String, String, String, String, String)

Initializes a new instance of the TreeNode class using the specified text, value, image URL, navigation URL, and target.

TreeNode()

Initializes a new instance of the TreeNode class without text or a value.

C#
public TreeNode();

Examples

The following code example demonstrates how to use this constructor to dynamically add a node to the TreeView control.

ASP.NET (C#)

<%@ 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 Page_Init(Object sender, EventArgs e)
  {
  
    if(!IsPostBack)
    {

      // Add the first tree to the TreeView control.
      CreateTree("Section 1");

      // Add the second tree to the TreeView control.
      CreateTree("Section 2");
    
    }

  }

  void CreateTree(String NodeText)
  {

    // Create the root node using the default constructor.
    TreeNode root = new TreeNode();
    root.Text = NodeText;

    // Use the ChildNodes property of the root TreeNode to add child nodes.
    // Create the node using the constructor that takes the text parameter.
    root.ChildNodes.Add(new TreeNode("Topic 1"));

    // Create the node using the constructor that takes the text and value parameters.
    root.ChildNodes.Add(new TreeNode("Topic 2", "Value 2"));

    // Create the node using the constructor that takes the text, value, 
    // and imageUrl parameters.
    root.ChildNodes.Add(new TreeNode("Topic 3", "Value 3", "Image1.jpg"));

    // Create the node using the constructor that takes the text, value, 
    // imageUrl, navigateUrl, and target parameters.
    root.ChildNodes.Add(new TreeNode("Topic 4", "Value 4", "Image1.jpg", "http://www.microsoft.com", "_blank"));

    // Add the root node to the Nodes collection of the TreeView control.
    DynamicTreeView.Nodes.Add(root);

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNode Constructor Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNode Constructor Example</h3>
      
      <asp:TreeView id="DynamicTreeView"
         EnableClientScript="false"
         ExpandDepth="2" 
         runat="server">
        
      </asp:TreeView>

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

Remarks

Use this constructor to initialize a new instance of the TreeNode class using the default values.

Poznámka

When this constructor is used, all properties in the TreeNode object are set to their default values. Be sure to set the properties, as necessary, after creating the object.

See also

Applies to

.NET Framework 4.8.1 a ďalšie verzie
Produkt Verzie
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

TreeNode(String)

Initializes a new instance of the TreeNode class using the specified text.

C#
public TreeNode(string text);

Parameters

text
String

The text that is displayed in the TreeView control for the node.

Examples

The following code example demonstrates how to use this constructor to dynamically add a node to the TreeView control.

ASP.NET (C#)

<%@ 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 Page_Init(Object sender, EventArgs e)
  {
  
    if(!IsPostBack)
    {

      // Add the first tree to the TreeView control.
      CreateTree("Section 1");

      // Add the second tree to the TreeView control.
      CreateTree("Section 2");
    
    }

  }

  void CreateTree(String NodeText)
  {

    // Create the root node using the default constructor.
    TreeNode root = new TreeNode();
    root.Text = NodeText;

    // Use the ChildNodes property of the root TreeNode to add child nodes.
    // Create the node using the constructor that takes the text parameter.
    root.ChildNodes.Add(new TreeNode("Topic 1"));

    // Create the node using the constructor that takes the text and value parameters.
    root.ChildNodes.Add(new TreeNode("Topic 2", "Value 2"));

    // Create the node using the constructor that takes the text, value, 
    // and imageUrl parameters.
    root.ChildNodes.Add(new TreeNode("Topic 3", "Value 3", "Image1.jpg"));

    // Create the node using the constructor that takes the text, value, 
    // imageUrl, navigateUrl, and target parameters.
    root.ChildNodes.Add(new TreeNode("Topic 4", "Value 4", "Image1.jpg", "http://www.microsoft.com", "_blank"));

    // Add the root node to the Nodes collection of the TreeView control.
    DynamicTreeView.Nodes.Add(root);

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNode Constructor Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNode Constructor Example</h3>
      
      <asp:TreeView id="DynamicTreeView"
         EnableClientScript="false"
         ExpandDepth="2" 
         runat="server">
        
      </asp:TreeView>

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

Remarks

Use this constructor to initialize a new instance of the TreeNode class using the text specified by the text parameter.

The following table shows the initial property value for an instance of TreeNode.

Property Initial value
Text The value of the text parameter.

See also

Applies to

.NET Framework 4.8.1 a ďalšie verzie
Produkt Verzie
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

TreeNode(String, String)

Initializes a new instance of the TreeNode class using the specified text and value.

C#
public TreeNode(string text, string value);

Parameters

text
String

The text that is displayed in the TreeView control for the node.

value
String

The supplemental data associated with the node, such as data used for handling postback events.

Examples

The following code example demonstrates how to use this constructor to dynamically add a node to the TreeView control.

ASP.NET (C#)

<%@ 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 Page_Init(Object sender, EventArgs e)
  {
  
    if(!IsPostBack)
    {

      // Add the first tree to the TreeView control.
      CreateTree("Section 1");

      // Add the second tree to the TreeView control.
      CreateTree("Section 2");
    
    }

  }

  void CreateTree(String NodeText)
  {

    // Create the root node using the default constructor.
    TreeNode root = new TreeNode();
    root.Text = NodeText;

    // Use the ChildNodes property of the root TreeNode to add child nodes.
    // Create the node using the constructor that takes the text parameter.
    root.ChildNodes.Add(new TreeNode("Topic 1"));

    // Create the node using the constructor that takes the text and value parameters.
    root.ChildNodes.Add(new TreeNode("Topic 2", "Value 2"));

    // Create the node using the constructor that takes the text, value, 
    // and imageUrl parameters.
    root.ChildNodes.Add(new TreeNode("Topic 3", "Value 3", "Image1.jpg"));

    // Create the node using the constructor that takes the text, value, 
    // imageUrl, navigateUrl, and target parameters.
    root.ChildNodes.Add(new TreeNode("Topic 4", "Value 4", "Image1.jpg", "http://www.microsoft.com", "_blank"));

    // Add the root node to the Nodes collection of the TreeView control.
    DynamicTreeView.Nodes.Add(root);

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNode Constructor Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNode Constructor Example</h3>
      
      <asp:TreeView id="DynamicTreeView"
         EnableClientScript="false"
         ExpandDepth="2" 
         runat="server">
        
      </asp:TreeView>

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

Remarks

Use this constructor to initialize a new instance of the TreeNode class using the text and value specified by the text and value parameters, respectively.

The following table shows initial property values for an instance of TreeNode.

Property Initial value
Text The value of the text parameter.
Value The value of the value parameter.

See also

Applies to

.NET Framework 4.8.1 a ďalšie verzie
Produkt Verzie
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

TreeNode(TreeView, Boolean)

Initializes a new instance of the TreeNode class using the specified owner.

C#
protected internal TreeNode(System.Web.UI.WebControls.TreeView owner, bool isRoot);

Parameters

owner
TreeView

The TreeView that will contain the new TreeNode.

isRoot
Boolean

true if the TreeNode is a root node; otherwise, false.

See also

Applies to

.NET Framework 4.8.1 a ďalšie verzie
Produkt Verzie
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

TreeNode(String, String, String)

Initializes a new instance of the TreeNode class using the specified text, value, and image URL.

C#
public TreeNode(string text, string value, string imageUrl);

Parameters

text
String

The text that is displayed in the TreeView control for the node.

value
String

The supplemental data associated with the node, such as data used for handling postback events.

imageUrl
String

The URL to an image that is displayed next to the node.

Examples

The following code example demonstrates how to use this constructor to dynamically add a node to the TreeView control.

ASP.NET (C#)

<%@ 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 Page_Init(Object sender, EventArgs e)
  {
  
    if(!IsPostBack)
    {

      // Add the first tree to the TreeView control.
      CreateTree("Section 1");

      // Add the second tree to the TreeView control.
      CreateTree("Section 2");
    
    }

  }

  void CreateTree(String NodeText)
  {

    // Create the root node using the default constructor.
    TreeNode root = new TreeNode();
    root.Text = NodeText;

    // Use the ChildNodes property of the root TreeNode to add child nodes.
    // Create the node using the constructor that takes the text parameter.
    root.ChildNodes.Add(new TreeNode("Topic 1"));

    // Create the node using the constructor that takes the text and value parameters.
    root.ChildNodes.Add(new TreeNode("Topic 2", "Value 2"));

    // Create the node using the constructor that takes the text, value, 
    // and imageUrl parameters.
    root.ChildNodes.Add(new TreeNode("Topic 3", "Value 3", "Image1.jpg"));

    // Create the node using the constructor that takes the text, value, 
    // imageUrl, navigateUrl, and target parameters.
    root.ChildNodes.Add(new TreeNode("Topic 4", "Value 4", "Image1.jpg", "http://www.microsoft.com", "_blank"));

    // Add the root node to the Nodes collection of the TreeView control.
    DynamicTreeView.Nodes.Add(root);

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNode Constructor Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNode Constructor Example</h3>
      
      <asp:TreeView id="DynamicTreeView"
         EnableClientScript="false"
         ExpandDepth="2" 
         runat="server">
        
      </asp:TreeView>

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

Remarks

Use this constructor to initialize a new instance of the TreeNode class using the text, value, and image URL specified by the text, value, and imageUrl parameters, respectively.

The following table shows initial property values for an instance of TreeNode.

Property Initial value
Text The value of the text parameter.
Value The value of the value parameter.
ImageUrl The value of the imageUrl parameter.

See also

Applies to

.NET Framework 4.8.1 a ďalšie verzie
Produkt Verzie
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1

TreeNode(String, String, String, String, String)

Initializes a new instance of the TreeNode class using the specified text, value, image URL, navigation URL, and target.

C#
public TreeNode(string text, string value, string imageUrl, string navigateUrl, string target);

Parameters

text
String

The text that is displayed in the TreeView control for the node.

value
String

The supplemental data associated with the node, such as data used for handling postback events.

imageUrl
String

The URL to an image that is displayed next to the node.

navigateUrl
String

The URL to link to when the node is clicked.

target
String

The target window or frame in which to display the Web page content linked to when the node is clicked.

Examples

The following code example demonstrates how to use this constructor to dynamically add a node to the TreeView control.

ASP.NET (C#)

<%@ 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 Page_Init(Object sender, EventArgs e)
  {
  
    if(!IsPostBack)
    {

      // Add the first tree to the TreeView control.
      CreateTree("Section 1");

      // Add the second tree to the TreeView control.
      CreateTree("Section 2");
    
    }

  }

  void CreateTree(String NodeText)
  {

    // Create the root node using the default constructor.
    TreeNode root = new TreeNode();
    root.Text = NodeText;

    // Use the ChildNodes property of the root TreeNode to add child nodes.
    // Create the node using the constructor that takes the text parameter.
    root.ChildNodes.Add(new TreeNode("Topic 1"));

    // Create the node using the constructor that takes the text and value parameters.
    root.ChildNodes.Add(new TreeNode("Topic 2", "Value 2"));

    // Create the node using the constructor that takes the text, value, 
    // and imageUrl parameters.
    root.ChildNodes.Add(new TreeNode("Topic 3", "Value 3", "Image1.jpg"));

    // Create the node using the constructor that takes the text, value, 
    // imageUrl, navigateUrl, and target parameters.
    root.ChildNodes.Add(new TreeNode("Topic 4", "Value 4", "Image1.jpg", "http://www.microsoft.com", "_blank"));

    // Add the root node to the Nodes collection of the TreeView control.
    DynamicTreeView.Nodes.Add(root);

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>TreeNode Constructor Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>TreeNode Constructor Example</h3>
      
      <asp:TreeView id="DynamicTreeView"
         EnableClientScript="false"
         ExpandDepth="2" 
         runat="server">
        
      </asp:TreeView>

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

Remarks

Use this constructor to initialize a new instance of the TreeNode class using the text, value, image and navigation URLs, and display target specified by the text, value, imageUrl, navigateUrl, and target parameters, respectively.

The following table shows initial property values for an instance of TreeNode.

Property Initial value
Text The value of the text parameter.
Value The value of the value parameter.
ImageUrl The value of the imageUrl parameter.
NavigateUrl The value of the navigateUrl parameter.
Target The value of the target parameter.

See also

Applies to

.NET Framework 4.8.1 a ďalšie verzie
Produkt Verzie
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1