Questa è la screen.
Quando seleziono il treeview, modifico la proprietà ImageList inserendo l'ImageList che ho creato io, visual studio automaticamente assegna a tutti i nodi esistenti l'immagine che sta nella posizione zero dell'ImageList. Questo è il codice Designer
codice:
#region Codice generato da Progettazione Windows Form
/// <summary>
/// Metodo necessario per il supporto della finestra di progettazione. Non modificare
/// il contenuto del metodo con l'editor di codice.
/// </summary>
public void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
System.Windows.Forms.ImageList imageList1;
System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(Form1));
System.Windows.Forms.TreeNode treeNode1 = new System.Windows.Forms.TreeNode("Nodo6");
System.Windows.Forms.TreeNode treeNode2 = new System.Windows.Forms.TreeNode("Nodo11");
System.Windows.Forms.TreeNode treeNode3 = new System.Windows.Forms.TreeNode("Nodo7", new System.Windows.Forms.TreeNode[] {
treeNode2});
System.Windows.Forms.TreeNode treeNode4 = new System.Windows.Forms.TreeNode("Nodo8");
System.Windows.Forms.TreeNode treeNode5 = new System.Windows.Forms.TreeNode("Nodo0", new System.Windows.Forms.TreeNode[] {
treeNode1,
treeNode3,
treeNode4});
System.Windows.Forms.TreeNode treeNode6 = new System.Windows.Forms.TreeNode("Nodo9");
System.Windows.Forms.TreeNode treeNode7 = new System.Windows.Forms.TreeNode("Nodo16");
System.Windows.Forms.TreeNode treeNode8 = new System.Windows.Forms.TreeNode("Nodo10", new System.Windows.Forms.TreeNode[] {
treeNode7});
System.Windows.Forms.TreeNode treeNode9 = new System.Windows.Forms.TreeNode("Nodo1", new System.Windows.Forms.TreeNode[] {
treeNode6,
treeNode8});
System.Windows.Forms.TreeNode treeNode10 = new System.Windows.Forms.TreeNode("Nodo2");
System.Windows.Forms.TreeNode treeNode11 = new System.Windows.Forms.TreeNode("Nodo12");
System.Windows.Forms.TreeNode treeNode12 = new System.Windows.Forms.TreeNode("Nodo15");
System.Windows.Forms.TreeNode treeNode13 = new System.Windows.Forms.TreeNode("Nodo13", new System.Windows.Forms.TreeNode[] {
treeNode12});
System.Windows.Forms.TreeNode treeNode14 = new System.Windows.Forms.TreeNode("Nodo3", new System.Windows.Forms.TreeNode[] {
treeNode11,
treeNode13});
System.Windows.Forms.TreeNode treeNode15 = new System.Windows.Forms.TreeNode("Nodo14");
System.Windows.Forms.TreeNode treeNode16 = new System.Windows.Forms.TreeNode("Nodo4", new System.Windows.Forms.TreeNode[] {
treeNode15});
this.treeView1 = new System.Windows.Forms.TreeView();
imageList1 = new System.Windows.Forms.ImageList(this.components);
this.SuspendLayout();
//
// imageList1
//
imageList1.ImageStream = ((System.Windows.Forms.ImageListStreamer)(resources.GetObject("imageList1.ImageStream")));
imageList1.TransparentColor = System.Drawing.Color.Transparent;
imageList1.Images.SetKeyName(0, "120px-Flag_of_Bangladesh.svg.png");
imageList1.Images.SetKeyName(1, "120px-Flag_of_the_Bahamas.svg.png");
imageList1.Images.SetKeyName(2, "120px-Flag_of_Algeria.svg.png");
imageList1.Images.SetKeyName(3, "120px-Flag_of_Austria.svg.png");
//
// treeView1
//
this.treeView1.ImageIndex = 0;
this.treeView1.ImageList = imageList1;
this.treeView1.Location = new System.Drawing.Point(105, 59);
this.treeView1.Name = "treeView1";
treeNode1.Name = "Nodo6";
treeNode1.Text = "Nodo6";
treeNode2.Name = "Nodo11";
treeNode2.Text = "Nodo11";
treeNode3.Name = "Nodo7";
treeNode3.Text = "Nodo7";
treeNode4.Name = "Nodo8";
treeNode4.Text = "Nodo8";
treeNode5.Name = "Nodo0";
treeNode5.Text = "Nodo0";
treeNode6.Name = "Nodo9";
treeNode6.Text = "Nodo9";
treeNode7.Name = "Nodo16";
treeNode7.Text = "Nodo16";
treeNode8.ImageKey = "120px-Flag_of_Bangladesh.svg.png";
treeNode8.Name = "Nodo10";
treeNode8.SelectedImageIndex = 0;
treeNode8.Text = "Nodo10";
treeNode9.ImageIndex = 1;
treeNode9.Name = "Nodo1";
treeNode9.Text = "Nodo1";
treeNode10.ImageKey = "120px-Flag_of_Algeria.svg.png";
treeNode10.Name = "Nodo2";
treeNode10.Text = "Nodo2";
treeNode11.Name = "Nodo12";
treeNode11.Text = "Nodo12";
treeNode12.Name = "Nodo15";
treeNode12.Text = "Nodo15";
treeNode13.Name = "Nodo13";
treeNode13.Text = "Nodo13";
treeNode14.ImageKey = "120px-Flag_of_Austria.svg.png";
treeNode14.Name = "Nodo3";
treeNode14.Text = "Nodo3";
treeNode15.Name = "Nodo14";
treeNode15.Text = "Nodo14";
treeNode16.Name = "Nodo4";
treeNode16.Text = "Nodo4";
this.treeView1.Nodes.AddRange(new System.Windows.Forms.TreeNode[] {
treeNode5,
treeNode9,
treeNode10,
treeNode14,
treeNode16});
this.treeView1.SelectedImageIndex = 0;
this.treeView1.Size = new System.Drawing.Size(345, 198);
this.treeView1.TabIndex = 0;
//
// Form1
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(528, 371);
this.Controls.Add(this.treeView1);
this.Name = "Form1";
this.Text = "Form1";
this.ResumeLayout(false);
}