OPC Studio User's Guide and Reference
CurrentNodeElement Property (UABrowseOutputs)
Example 



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OpcLabs.EasyOpcForms Assembly > OpcLabs.EasyOpc.UA.Forms.Browsing Namespace > UABrowseOutputs Class : CurrentNodeElement Property
Contains information gathered about the current node.
Syntax
'Declaration
 
Public Property CurrentNodeElement As UABrowseNodeElement
 
'Usage
 
Dim instance As UABrowseOutputs
Dim value As UABrowseNodeElement
 
instance.CurrentNodeElement = value
 
value = instance.CurrentNodeElement

Property Value

The value of this property cannot be null (Nothing in Visual Basic).

Remarks

The getter method of this property is pure, i.e. it does not have observable side effects.

Example
// This example shows how to allow browsing for an OPC Unified Architecture node by placing a browsing control on the form.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.

using System;
using System.Windows.Forms;
using OpcLabs.BaseLib;
using OpcLabs.EasyOpc.UA.Forms.Browsing;

namespace UAFormsDocExamples._UABrowseControl
{
    public partial class UsageForm : Form
    {
        public UsageForm()
        {
            InitializeComponent();
        }

        private void getOutputsButton_Click(object sender, EventArgs e)
        {
            // Obtain the current node element.
            UABrowseNodeElement currentNodeElement = uaBrowseControl1.Outputs.CurrentNodeElement;

            // Display the present parts of the current node element in the outputs text text box.
            outputsTextBox.Text = "";
            if (!(currentNodeElement.HostElement is null))
                outputsTextBox.Text += $"{nameof(UABrowseNodeElement.HostElement)}: {currentNodeElement.HostElement}\r\n";
            if (!(currentNodeElement.DiscoveryElement is null))
                outputsTextBox.Text += $"{nameof(UABrowseNodeElement.DiscoveryElement)}: {currentNodeElement.DiscoveryElement}\r\n";
            if (!(currentNodeElement.NodeElement is null))
                outputsTextBox.Text += $"{nameof(UABrowseNodeElement.NodeElement)}: {currentNodeElement.NodeElement}\r\n";
        }

        private void uaBrowseControl1_BrowseFailure(object sender, FailureEventArgs e)
        {
            // Append the event name and its arguments to the browsing events text box.
            browsingEventsTextBox.Text += $"{nameof(UABrowseControl.BrowseFailure)}: {e}\r\n";
        }

        private void uaBrowseControl1_CurrentNodeChanged(object sender, EventArgs e)
        {
            // Append the event name and the current node element to the browsing events text box.
            browsingEventsTextBox.Text += $"{nameof(UABrowseControl.CurrentNodeChanged)}; {uaBrowseControl1.Outputs.CurrentNodeElement}\r\n";
        }

        private void uaBrowseControl1_NodeDoubleClick(object sender, EventArgs e)
        {
            // Append the event name to the browsing events text box.
            browsingEventsTextBox.Text += $"{nameof(UABrowseControl.NodeDoubleClick)}\r\n";
        }

        private void uaBrowseControl1_SelectionChanged(object sender, EventArgs e)
        {
            // Append the event name to the browsing events text box.
            browsingEventsTextBox.Text += $"{nameof(UABrowseControl.SelectionChanged)}\r\n";
        }

        private void setInputsButton_Click(object sender, EventArgs e)
        {
            // Set the current node to our pre-defined OPC UA server.
            uaBrowseControl1.InputsOutputs.CurrentNodeDescriptor.EndpointDescriptor = "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer";
        }
    }
}
namespace UAFormsDocExamples._UABrowseControl
{
    partial class UsageForm
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.uaBrowseControl1 = new OpcLabs.EasyOpc.UA.Forms.Browsing.UABrowseControl();
            this.setInputsButton = new System.Windows.Forms.Button();
            this.getOutputsButton = new System.Windows.Forms.Button();
            this.label1 = new System.Windows.Forms.Label();
            this.outputsTextBox = new System.Windows.Forms.TextBox();
            this.browsingEventsTextBox = new System.Windows.Forms.TextBox();
            ((System.ComponentModel.ISupportInitialize)(this.uaBrowseControl1)).BeginInit();
            this.SuspendLayout();
            // 
            // uaBrowseControl1
            // 
            this.uaBrowseControl1.Location = new System.Drawing.Point(13, 42);
            this.uaBrowseControl1.MinimumSize = new System.Drawing.Size(135, 150);
            this.uaBrowseControl1.Name = "uaBrowseControl1";
            this.uaBrowseControl1.Size = new System.Drawing.Size(450, 300);
            this.uaBrowseControl1.TabIndex = 0;
            this.uaBrowseControl1.BrowseFailure += new OpcLabs.BaseLib.FailureEventHandler(this.uaBrowseControl1_BrowseFailure);
            this.uaBrowseControl1.CurrentNodeChanged += new System.EventHandler(this.uaBrowseControl1_CurrentNodeChanged);
            this.uaBrowseControl1.NodeDoubleClick += new System.EventHandler(this.uaBrowseControl1_NodeDoubleClick);
            this.uaBrowseControl1.SelectionChanged += new System.EventHandler(this.uaBrowseControl1_SelectionChanged);
            // 
            // setInputsButton
            // 
            this.setInputsButton.Location = new System.Drawing.Point(13, 13);
            this.setInputsButton.Name = "setInputsButton";
            this.setInputsButton.Size = new System.Drawing.Size(75, 23);
            this.setInputsButton.TabIndex = 1;
            this.setInputsButton.Text = "&Set inputs";
            this.setInputsButton.UseVisualStyleBackColor = true;
            this.setInputsButton.Click += new System.EventHandler(this.setInputsButton_Click);
            // 
            // getOutputsButton
            // 
            this.getOutputsButton.Location = new System.Drawing.Point(13, 349);
            this.getOutputsButton.Name = "getOutputsButton";
            this.getOutputsButton.Size = new System.Drawing.Size(75, 23);
            this.getOutputsButton.TabIndex = 2;
            this.getOutputsButton.Text = "&Get outputs";
            this.getOutputsButton.UseVisualStyleBackColor = true;
            this.getOutputsButton.Click += new System.EventHandler(this.getOutputsButton_Click);
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(481, 42);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(88, 13);
            this.label1.TabIndex = 3;
            this.label1.Text = "&Browsing events:";
            // 
            // outputsTextBox
            // 
            this.outputsTextBox.Location = new System.Drawing.Point(13, 379);
            this.outputsTextBox.Multiline = true;
            this.outputsTextBox.Name = "outputsTextBox";
            this.outputsTextBox.ReadOnly = true;
            this.outputsTextBox.Size = new System.Drawing.Size(951, 59);
            this.outputsTextBox.TabIndex = 4;
            // 
            // browsingEventsTextBox
            // 
            this.browsingEventsTextBox.Location = new System.Drawing.Point(484, 59);
            this.browsingEventsTextBox.Multiline = true;
            this.browsingEventsTextBox.Name = "browsingEventsTextBox";
            this.browsingEventsTextBox.ReadOnly = true;
            this.browsingEventsTextBox.Size = new System.Drawing.Size(480, 283);
            this.browsingEventsTextBox.TabIndex = 5;
            // 
            // UsageForm
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(976, 450);
            this.Controls.Add(this.browsingEventsTextBox);
            this.Controls.Add(this.outputsTextBox);
            this.Controls.Add(this.label1);
            this.Controls.Add(this.getOutputsButton);
            this.Controls.Add(this.setInputsButton);
            this.Controls.Add(this.uaBrowseControl1);
            this.Name = "UsageForm";
            this.Text = "UsageForm";
            ((System.ComponentModel.ISupportInitialize)(this.uaBrowseControl1)).EndInit();
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private OpcLabs.EasyOpc.UA.Forms.Browsing.UABrowseControl uaBrowseControl1;
        private System.Windows.Forms.Button setInputsButton;
        private System.Windows.Forms.Button getOutputsButton;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.TextBox outputsTextBox;
        private System.Windows.Forms.TextBox browsingEventsTextBox;
    }
}
Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

See Also