![]() ![]() If you apply this method to the control’s root node, it will clear the control. The Clear method removes all the child nodes from the current node. " continents on the control") Code language: VB.NET ( vbnet ) Again, you can simplify this expression by using an intermediate TreeNode object: Dim Continents As TreeNode Returns the number of countries in the Countries example. The expression TreeView1.Nodes( 0).Nodes.Count Code language: VB.NET ( vbnet ) In the case of the Countries example, it returns the value 1. Returns the number of all nodes in the first level of the control. The expression Code language: VB.NET ( vbnet ) Again, this is not the total number of nodes in the control, just the number of nodes in the current Nodes collection. The Count property returns the number of nodes in the Nodes collection. The Nodes collection exposes the usual members of a collection. ( "Manchester") Code language: VB.NET ( vbnet ) The Nodes Collection Members Then you can continue adding states under another country as follows: StateNode = ( "United Kingdom") ( "Auburn") Code language: VB.NET ( vbnet ) The Add method actually returns a TreeNode object that represents the newly added node, so you can add a state and a few cities by using statements such as the following: Dim StateNode As TreeNode To add yet another level of nodes, the city nodes, create a new variable that represents a specific state. Likewise, this node has its own Nodes collection, which contains the states under the specific country.Ĭ( "California") Code language: VB.NET ( vbnet ) If you want to change the appearance of the node United States, type a period after the preceding expression to access its properties (the NodeFont property to set its font, the ForeColor property to set it color, the ImageIndex property, and so on). The first node in this collection is United States, and you can access it with the expression TreeView1.Nodes(0).Nodes(0). Each node in this collection is a country name. ![]() Under this node, there is a collection of nodes, the TreeView1.Nodes(0).Nodes collection. TreeView1.Nodes(0) is the first root node, the Countries node. Let’s take a closer look at these expressions. Text)ĭebug.WriteLine(TreeView1.Nodes( 0).Nodes( 0).Nodes( 1). Text)ĭebug.WriteLine(TreeView1.Nodes( 0).Nodes( 0). The following statements print the strings shown highlighted below them (these strings are not part of the statements they’re the output that the statements produce): Debug.WriteLine(TreeView1.Nodes( 0). The caption of the second node on the same level is TreeView1.Nodes(1).Text, and so on. TreeView1.Nodes(0).Text is the caption of the root node on the control. The Text property returns the node’s value, which is a string. To access the first node, use the expression TreeView.Nodes(0) (this is the Globe node in our example). ![]()
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