Csharp/CSharp Tutorial/GUI Windows Forms/ListBox
Содержание
- 1 Add ContextMenu to ListBox
- 2 Add Items to ListBox
- 3 Add text in the TextBox to the ListBox
- 4 Fills a ListBox with data from Database
- 5 ListBox Events: SelectedIndexChanged, SelectedValueChanged, DataSourceChanged, DisplayMemberChanged, ValueMemberChanged
- 6 ListBox Items Add
- 7 ListBox Items Add a Range
- 8 ListBox Selection Mode
- 9 Set the TopIndex property of the ListBox to ensure the most recently added items are visible
- 10 Use RadioButton to control ListBox selection mode
Add ContextMenu to ListBox
<source lang="csharp">using System; using System.Drawing; using System.Collections; using System.ruponentModel; using System.Windows.Forms; using System.Data; public class ListBoxContextMenu : System.Windows.Forms.Form {
private System.Windows.Forms.Button btnDone;
private System.Windows.Forms.TextBox textBox1;
private System.Windows.Forms.Button btnAdd;
private System.Windows.Forms.ListBox listBox1;
private System.Windows.Forms.ContextMenu contextMenu1;
private System.Windows.Forms.MenuItem menuItem1;
private System.Windows.Forms.MenuItem menuItem2;
private System.Windows.Forms.MenuItem menuItem3;
private System.Windows.Forms.MenuItem menuItem4;
private System.ruponentModel.Container components = null;
public ListBoxContextMenu()
{
InitializeComponent();
}
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
private void InitializeComponent()
{
this.btnDone = new System.Windows.Forms.Button();
this.textBox1 = new System.Windows.Forms.TextBox();
this.btnAdd = new System.Windows.Forms.Button();
this.listBox1 = new System.Windows.Forms.ListBox();
this.contextMenu1 = new System.Windows.Forms.ContextMenu();
this.menuItem1 = new System.Windows.Forms.MenuItem();
this.menuItem2 = new System.Windows.Forms.MenuItem();
this.menuItem3 = new System.Windows.Forms.MenuItem();
this.menuItem4 = new System.Windows.Forms.MenuItem();
this.SuspendLayout();
//
// btnDone
//
this.btnDone.Location = new System.Drawing.Point(208, 16);
this.btnDone.Name = "btnDone";
this.btnDone.TabIndex = 3;
this.btnDone.Text = "Done";
this.btnDone.Click += new System.EventHandler(this.btnDone_Click);
//
// textBox1
//
this.textBox1.Location = new System.Drawing.Point(16, 88);
this.textBox1.Name = "textBox1";
this.textBox1.TabIndex = 5;
this.textBox1.Text = "";
//
// btnAdd
//
this.btnAdd.Location = new System.Drawing.Point(16, 120);
this.btnAdd.Name = "btnAdd";
this.btnAdd.TabIndex = 6;
this.btnAdd.Text = "Add";
this.btnAdd.Click += new System.EventHandler(this.btnAdd_Click);
//
// listBox1
//
this.listBox1.ContextMenu = this.contextMenu1;
this.listBox1.Location = new System.Drawing.Point(16, 8);
this.listBox1.Name = "listBox1";
this.listBox1.Size = new System.Drawing.Size(120, 69);
this.listBox1.TabIndex = 7;
//
// contextMenu1
//
this.contextMenu1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
this.menuItem1,
this.menuItem2,
this.menuItem3,
this.menuItem4});
//
// menuItem1
//
this.menuItem1.Index = 0;
this.menuItem1.Text = "Move Down";
this.menuItem1.Click += new System.EventHandler(this.ctxtMenuClick);
//
// menuItem2
//
this.menuItem2.Index = 1;
this.menuItem2.Text = "Move up";
this.menuItem2.Click += new System.EventHandler(this.ctxtMenuClick);
//
// menuItem3
//
this.menuItem3.Index = 2;
this.menuItem3.Text = "Delete";
this.menuItem3.Click += new System.EventHandler(this.ctxtMenuClick);
//
// menuItem4
//
this.menuItem4.Index = 3;
this.menuItem4.Text = "Duplicate";
this.menuItem4.Click += new System.EventHandler(this.ctxtMenuClick);
//
// ListBoxContextMenu
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 266);
this.Controls.AddRange(new System.Windows.Forms.Control[] {
this.listBox1,
this.btnAdd,
this.textBox1,
this.btnDone});
this.Name = "ListBoxContextMenu";
this.ResumeLayout(false);
}
#endregion
[STAThread]
static void Main()
{
Application.Run(new ListBoxContextMenu());
}
private void btnDone_Click(object sender, System.EventArgs e)
{
Application.Exit();
}
private void btnAdd_Click(object sender, System.EventArgs e)
{
listBox1.Items.Add(textBox1.Text);
textBox1.Text = "";
}
private void ctxtMenuClick(object sender, System.EventArgs e)
{
if ( listBox1.SelectedIndex != -1 )
{
MenuItem mi = (MenuItem) sender;
MessageBox.Show(mi.Text + " on " + listBox1.SelectedItem,"Context Menu", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
}else{
MessageBox.Show("Please select an item","Context Menu Tester", MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
}
}
}</source>
Add Items to ListBox
<source lang="csharp">using System; using System.Drawing; using System.Collections; using System.ruponentModel; using System.Windows.Forms; using System.Data; public class ListBoxItemAdd : System.Windows.Forms.Form {
private System.Windows.Forms.Button button1;
private System.Windows.Forms.TextBox textBox1;
private System.Windows.Forms.ListBox listBox1;
private System.ruponentModel.Container components = null;
public ListBoxItemAdd()
{
InitializeComponent();
}
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.textBox1 = new System.Windows.Forms.TextBox();
this.listBox1 = new System.Windows.Forms.ListBox();
this.SuspendLayout();
this.button1.Font = new System.Drawing.Font("Verdana", 8.25F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
this.button1.Location = new System.Drawing.Point(16, 16);
this.button1.Name = "button1";
this.button1.Size = new System.Drawing.Size(80, 32);
this.button1.TabIndex = 0;
this.button1.Text = "Add";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// textBox1
//
this.textBox1.AutoSize = false;
this.textBox1.Location = new System.Drawing.Point(112, 16);
this.textBox1.Name = "textBox1";
this.textBox1.Size = new System.Drawing.Size(168, 32);
this.textBox1.TabIndex = 1;
this.textBox1.Text = "textBox1";
//
// listBox1
//
this.listBox1.BackColor = System.Drawing.Color.Red;
this.listBox1.ForeColor = System.Drawing.SystemColors.HighlightText;
this.listBox1.Location = new System.Drawing.Point(8, 64);
this.listBox1.Name = "listBox1";
this.listBox1.Size = new System.Drawing.Size(272, 238);
this.listBox1.TabIndex = 2;
//
// ListBoxItemAdd
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(328, 318);
this.Controls.AddRange(new System.Windows.Forms.Control[] {
this.listBox1,
this.textBox1,
this.button1});
this.Name = "ListBoxItemAdd";
this.Text = "ListBoxItemAdd";
this.ResumeLayout(false);
}
[STAThread]
static void Main()
{
Application.Run(new ListBoxItemAdd());
}
private void button1_Click(object sender, System.EventArgs e)
{
listBox1.Items.Add(textBox1.Text);
}
}</source>
Add text in the TextBox to the ListBox
<source lang="csharp">using System; using System.Drawing; using System.Windows.Forms;
public class ListBoxTextBoxButton : Form {
private TextBox data;
private ListBox results;
public ListBoxTextBoxButton()
{
Size = new Size(400, 380);
Label label1 = new Label();
label1.Parent = this;
label1.Text = "Enter text:";
label1.AutoSize = true;
label1.Location = new Point(10, 10);
data = new TextBox();
data.Parent = this;
data.Size = new Size(200, 2 * Font.Height);
data.Location = new Point(10, 35);
results = new ListBox();
results.Parent = this;
results.Location = new Point(10, 65);
results.Size = new Size(350, 20 * Font.Height);
Button checkit = new Button();
checkit.Parent = this;
checkit.Text = "test";
checkit.Location = new Point(235,32);
checkit.Size = new Size(7 * Font.Height, 2 * Font.Height);
checkit.Click += new EventHandler(ButtonOnClick);
}
void ButtonOnClick(object obj, EventArgs ea)
{
results.Items.Add(data.Text);
data.Clear();
}
public static void Main()
{
Application.Run(new ListBoxTextBoxButton());
}
}</source>
Fills a ListBox with data from Database
<source lang="csharp">using System; using System.Windows.Forms; using System.Data.SqlClient; public class DataReaderTest : Form {
private ListBox lstNames;
private string connectionString = "Data Source=localhost;Initial Catalog=Northwind;Integrated Security=SSPI";
public DataReaderTest()
{
lstNames = new ListBox();
lstNames.Dock = DockStyle.Fill;
Controls.Add(lstNames);
Load += new EventHandler(DataReaderTest_Load);
}
public static void Main()
{
DataReaderTest t = new DataReaderTest();
Application.Run(t);
}
private void DataReaderTest_Load(object sender, System.EventArgs e)
{
string SQL = "SELECT ContactName FROM Customers";
SqlConnection con = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(SQL, con);
SqlDataReader r = null;
con.Open();
r = cmd.ExecuteReader();
while (r.Read()) {
lstNames.Items.Add(r["ContactName"]);
}
con.Close();
}
}</source>
ListBox Events: SelectedIndexChanged, SelectedValueChanged, DataSourceChanged, DisplayMemberChanged, ValueMemberChanged
<source lang="csharp">using System; using System.Drawing; using System.Collections; using System.ruponentModel; using System.Windows.Forms; using System.Data; using System.Data.SqlClient; public class Employee
public string ID;
public string Name ;
public Employee(string strName, string strID)
{
this.ID = strID;
this.Name = strName;
}
public override string ToString()
{
return this.ID + " : " + this.Name;
}
public class Form1 : System.Windows.Forms.Form {
private System.Windows.Forms.GroupBox groupBox1;
private System.Windows.Forms.RadioButton rbAuthors;
private System.Windows.Forms.RadioButton rbEmployees;
private System.Windows.Forms.ListBox lb;
private DataTable dataTable;
private ArrayList Employees = new ArrayList();
private System.ruponentModel.Container components = null;
public Form1()
{
InitializeComponent();
lb.Items.Add("A");
lb.Items.Add("B");
lb.Items.Add("C");
lb.Items.Add("D");
lb.Items.Add("E");
lb.SelectedIndex = 0;
// populate the arraylist for later use.
Employees.Add(new Employee("A", "1"));
Employees.Add(new Employee("B", "2"));
Employees.Add(new Employee("C", "3"));
Employees.Add(new Employee("D", "4"));
Employees.Add(new Employee("E", "5"));
Employees.Add(new Employee("F", "6"));
Employees.Add(new Employee("G", "7"));
}
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
private void InitializeComponent()
{
this.lb = new System.Windows.Forms.ListBox();
this.groupBox1 = new System.Windows.Forms.GroupBox();
this.rbEmployees = new System.Windows.Forms.RadioButton();
this.rbAuthors = new System.Windows.Forms.RadioButton();
this.groupBox1.SuspendLayout();
this.SuspendLayout();
//
// lb
//
this.lb.Location = new System.Drawing.Point(16, 8);
this.lb.Name = "lb";
this.lb.Size = new System.Drawing.Size(232, 212);
this.lb.TabIndex = 0;
this.lb.DisplayMemberChanged += new System.EventHandler(this.lb_DisplayMemberChanged);
this.lb.ValueMemberChanged += new System.EventHandler(this.lb_ValueMemberChanged);
this.lb.DataSourceChanged += new System.EventHandler(this.lb_DataSourceChanged);
this.lb.SelectedValueChanged += new System.EventHandler(this.lb_SelectedValueChanged);
this.lb.SelectedIndexChanged += new System.EventHandler(this.lb_SelectedIndexChanged);
//
// groupBox1
//
this.groupBox1.Controls.AddRange(new System.Windows.Forms.Control[] {
this.rbEmployees,
this.rbAuthors});
this.groupBox1.Location = new System.Drawing.Point(16, 240);
this.groupBox1.Name = "groupBox1";
this.groupBox1.TabIndex = 1;
this.groupBox1.TabStop = false;
this.groupBox1.Text = "DataSource";
//
// rbEmployees
//
this.rbEmployees.Location = new System.Drawing.Point(24, 56);
this.rbEmployees.Name = "rbEmployees";
this.rbEmployees.TabIndex = 1;
this.rbEmployees.Text = "Employee\"s";
this.rbEmployees.CheckedChanged += new System.EventHandler(this.rb_CheckedChanged);
//
// rbAuthors
//
this.rbAuthors.Checked = true;
this.rbAuthors.Location = new System.Drawing.Point(24, 32);
this.rbAuthors.Name = "rbAuthors";
this.rbAuthors.TabIndex = 0;
this.rbAuthors.TabStop = true;
this.rbAuthors.Text = "Authors";
this.rbAuthors.CheckedChanged += new System.EventHandler(this.rb_CheckedChanged);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(264, 389);
this.Controls.AddRange(new System.Windows.Forms.Control[] {
this.groupBox1,
this.lb});
this.Name = "Form1";
this.Text = "Form1";
this.Load += new System.EventHandler(this.Form1_Load);
this.groupBox1.ResumeLayout(false);
this.ResumeLayout(false);
}
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void rb_CheckedChanged(object sender, System.EventArgs e)
{
lb.DataSource = Employees;
lb.DisplayMember = "Name";
lb.ValueMember = "ID";
}
private void lb_SelectedIndexChanged(object sender, System.EventArgs e)
{
MessageBox.Show(lb.SelectedIndex.ToString()+ "\n" + lb.GetItemText(lb.SelectedItem),"lb_SelectedIndexChanged");
}
private void lb_SelectedValueChanged(object sender, System.EventArgs e)
{
MessageBox.Show(lb.GetItemText(lb.SelectedItem),"lb_SelectedValueChanged");
}
private void lb_DataSourceChanged(object sender, System.EventArgs e)
{
MessageBox.Show(lb.DataSource.ToString(), "lb_DataSourceChanged");
}
private void lb_DisplayMemberChanged(object sender, System.EventArgs e)
{
MessageBox.Show(lb.DisplayMember.ToString(), "lb_DisplayMemberChanged");
}
private void lb_ValueMemberChanged(object sender, System.EventArgs e)
{
MessageBox.Show(lb.ValueMember.ToString(), "lb_ValueMemberChanged");
}
private void Form1_Load(object sender, System.EventArgs e)
{
this.lb.SelectedValueChanged += new System.EventHandler(this.lb_SelectedValueChanged);
this.lb.SelectedIndexChanged += new System.EventHandler(this.lb_SelectedIndexChanged);
}
}</source>
ListBox Items Add
<source lang="csharp">using System; using System.Drawing; using System.Windows.Forms; using System.Data; using System.Data.SqlClient; public class ListBoxItemAdd : Form{
ListBox lb;
public ListBoxItemAdd()
{
Size = new Size(300,400);
lb = new ListBox();
lb.Parent = this;
lb.Location = new Point(10,10);
lb.Size = new Size(ClientSize.Width - 20, Height - 200);
lb.Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right | AnchorStyles.Bottom;
lb.BorderStyle = BorderStyle.Fixed3D;
lb.BeginUpdate();
for (int i = 0; i < 5; i++)
{
lb.Items.Add(i);
}
lb.Items.Add("12345");
lb.Items.Add("67890");
lb.EndUpdate();
}
static void Main()
{
Application.Run(new ListBoxItemAdd());
}
}</source>
ListBox Items Add a Range
<source lang="csharp">using System; using System.Drawing; using System.Windows.Forms; using System.Data; using System.Data.SqlClient; public class ListBoxItemAddRange : Form{
ListBox lb;
public ListBoxItemAddRange()
{
Size = new Size(300,400);
lb = new ListBox();
lb.Parent = this;
lb.Location = new Point(10,10);
lb.Size = new Size(ClientSize.Width - 20, Height - 200);
lb.Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right | AnchorStyles.Bottom;
lb.BorderStyle = BorderStyle.Fixed3D;
lb.BeginUpdate();
string[] arNames = new string[5];
for(int i = 0;i<5;i++){
arNames[i] = "I";
}
lb.Items.AddRange(arNames);
lb.Items.Add("12345");
lb.Items.Add("67890");
lb.EndUpdate();
}
static void Main()
{
Application.Run(new ListBoxItemAddRange());
}
}</source>
ListBox Selection Mode
<source lang="csharp">using System; using System.Drawing; using System.Windows.Forms; using System.Data; using System.Data.SqlClient; public class ListBoxSelectionMode : Form {
ListBox lb;
RadioButton rdoMultiExtended;
RadioButton rdoMultiSimple;
RadioButton rdoMultiOne;
TextBox txtTop;
Button btnTop;
public ListBoxSelectionMode()
{
int xSize, ySize;
Size = new Size(300,400);
lb = new ListBox();
lb.Parent = this;
lb.Location = new Point(10,10);
lb.Size = new Size(ClientSize.Width - 20, Height - 200);
lb.Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right | AnchorStyles.Bottom;
lb.BorderStyle = BorderStyle.Fixed3D;
lb.MultiColumn = true;
lb.ScrollAlwaysVisible = true;
GroupBox grpMulti = new GroupBox();
grpMulti.Parent = this;
grpMulti.Text = "MultiSelect";
grpMulti.Location = new Point(lb.Left, lb.Bottom + 25);
grpMulti.Anchor = AnchorStyles.Left | AnchorStyles.Bottom;
rdoMultiOne = new RadioButton();
rdoMultiOne.Parent = grpMulti;
rdoMultiOne.Text = "One";
rdoMultiOne.Tag = SelectionMode.One;
rdoMultiOne.Checked = true;
rdoMultiOne.Location = new Point(10,15);
rdoMultiOne.CheckedChanged += new System.EventHandler(rdoMulti_CheckedChanged);
rdoMultiSimple = new RadioButton();
rdoMultiSimple.Parent = grpMulti;
rdoMultiSimple.Text = "Multi-Simple";
rdoMultiSimple.Tag = SelectionMode.MultiSimple;
rdoMultiSimple.Location = new Point(10, rdoMultiOne.Bottom);
rdoMultiSimple.CheckedChanged += new System.EventHandler(rdoMulti_CheckedChanged);
rdoMultiExtended = new RadioButton();
rdoMultiExtended.Parent = grpMulti;
rdoMultiExtended.Text = "Multi-Extended";
rdoMultiExtended.Tag = SelectionMode.MultiExtended;
rdoMultiExtended.Location = new Point(10, rdoMultiSimple.Bottom);
rdoMultiExtended.CheckedChanged += new System.EventHandler(rdoMulti_CheckedChanged);
xSize = (int)(Font.Height * .75) * rdoMultiExtended.Text.Length;
ySize = ((int)rdoMultiOne.Height * 3) + 20;
grpMulti.Size = new Size(xSize, ySize);
Panel pnlTop = new Panel();
pnlTop.Parent = this;
pnlTop.Location = new Point(lb.Left, grpMulti.Bottom + 10);
pnlTop.Anchor = AnchorStyles.Left | AnchorStyles.Bottom;
Label lblTop = new Label();
lblTop.Parent = pnlTop;
lblTop.Text = "TopIndex: ";
xSize = ((int)(Font.Height * .5) * lblTop.Text.Length);
lblTop.Size = new Size(xSize, Font.Height + 10);
txtTop = new TextBox();
txtTop.Parent = pnlTop;
txtTop.Location = new Point(lblTop.Right, lblTop.Top);
txtTop.Text = lb.TopIndex.ToString();
txtTop.Size = new Size((int)(Font.Height * .75) * 3,
Font.Height + 10);
btnTop = new Button();
btnTop.Parent = pnlTop;
btnTop.Text = "Update";
btnTop.Location = new Point(txtTop.Right + 10, txtTop.Top);
btnTop.Click += new System.EventHandler(btnTop_Click);
lb.Items.Add("12345");
lb.Items.Add("67890");
lb.Items.Add("7890");
lb.Items.Add("890");
}
static void Main()
{
Application.Run(new ListBoxSelectionMode());
}
private void rdoMulti_CheckedChanged(object sender, EventArgs e)
{
RadioButton rdo = (RadioButton)sender;
lb.SelectionMode = (SelectionMode)rdo.Tag;
}
private void btnTop_Click(object sender, EventArgs e)
{
txtTop.Text = lb.TopIndex.ToString();
}
}</source>
Set the TopIndex property of the ListBox to ensure the most recently added items are visible
<source lang="csharp">using System; using System.Windows.Forms; public class ListBoxItemVisibleFormDemo{
[STAThread]
public static void Main(string[] args)
{
Application.Run(new ListBoxItemVisibleForm());
}
} public partial class ListBoxItemVisibleForm : Form {
private int counter = 0;
public ListBoxItemVisibleForm()
{
InitializeComponent();
}
private void cmdTest_Click(object sender, EventArgs e)
{
for (int i = 0; i < 200; i++)
{
counter++;
listBox1.Items.Add("Item " + counter.ToString());
}
listBox1.TopIndex = listBox1.Items.Count - 1;
listBox1.SelectedIndex = listBox1.Items.Count - 1;
}
} partial class ListBoxItemVisibleForm {
private System.Windows.Forms.ListBox listBox1;
private System.Windows.Forms.Button cmdTest;
private System.ruponentModel.IContainer components = null;
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
private void InitializeComponent()
{
this.listBox1 = new System.Windows.Forms.ListBox();
this.cmdTest = new System.Windows.Forms.Button();
this.SuspendLayout();
this.listBox1.FormattingEnabled = true;
this.listBox1.Location = new System.Drawing.Point(8, 8);
this.listBox1.Name = "listBox1";
this.listBox1.Size = new System.Drawing.Size(248, 160);
this.listBox1.TabIndex = 0;
this.cmdTest.Location = new System.Drawing.Point(12, 184);
this.cmdTest.Name = "cmdTest";
this.cmdTest.Size = new System.Drawing.Size(132, 28);
this.cmdTest.TabIndex = 1;
this.cmdTest.Text = "Test Scroll";
this.cmdTest.Click += new System.EventHandler(this.cmdTest_Click);
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(292, 246);
this.Controls.Add(this.cmdTest);
this.Controls.Add(this.listBox1);
this.Name = "ListBoxItemVisibleForm";
this.Text = "ListBoxItemVisibleForm";
this.ResumeLayout(false);
}
}</source>
Use RadioButton to control ListBox selection mode
<source lang="csharp">using System; using System.Drawing; using System.Windows.Forms; using System.Data; using System.Data.SqlClient; public class ListBoxSelectionMode : Form {
ListBox lb;
RadioButton rdoMultiExtended;
RadioButton rdoMultiSimple;
RadioButton rdoMultiOne;
TextBox txtTop;
Button btnTop;
public ListBoxSelectionMode()
{
int xSize, ySize;
Size = new Size(300,400);
lb = new ListBox();
lb.Parent = this;
lb.Location = new Point(10,10);
lb.Size = new Size(ClientSize.Width - 20, Height - 200);
lb.Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right | AnchorStyles.Bottom;
lb.BorderStyle = BorderStyle.Fixed3D;
lb.MultiColumn = true;
lb.ScrollAlwaysVisible = true;
GroupBox grpMulti = new GroupBox();
grpMulti.Parent = this;
grpMulti.Text = "MultiSelect";
grpMulti.Location = new Point(lb.Left, lb.Bottom + 25);
grpMulti.Anchor = AnchorStyles.Left | AnchorStyles.Bottom;
rdoMultiOne = new RadioButton();
rdoMultiOne.Parent = grpMulti;
rdoMultiOne.Text = "One";
rdoMultiOne.Tag = SelectionMode.One;
rdoMultiOne.Checked = true;
rdoMultiOne.Location = new Point(10,15);
rdoMultiOne.CheckedChanged += new System.EventHandler(rdoMulti_CheckedChanged);
rdoMultiSimple = new RadioButton();
rdoMultiSimple.Parent = grpMulti;
rdoMultiSimple.Text = "Multi-Simple";
rdoMultiSimple.Tag = SelectionMode.MultiSimple;
rdoMultiSimple.Location = new Point(10, rdoMultiOne.Bottom);
rdoMultiSimple.CheckedChanged += new System.EventHandler(rdoMulti_CheckedChanged);
rdoMultiExtended = new RadioButton();
rdoMultiExtended.Parent = grpMulti;
rdoMultiExtended.Text = "Multi-Extended";
rdoMultiExtended.Tag = SelectionMode.MultiExtended;
rdoMultiExtended.Location = new Point(10, rdoMultiSimple.Bottom);
rdoMultiExtended.CheckedChanged += new System.EventHandler(rdoMulti_CheckedChanged);
xSize = (int)(Font.Height * .75) * rdoMultiExtended.Text.Length;
ySize = ((int)rdoMultiOne.Height * 3) + 20;
grpMulti.Size = new Size(xSize, ySize);
Panel pnlTop = new Panel();
pnlTop.Parent = this;
pnlTop.Location = new Point(lb.Left, grpMulti.Bottom + 10);
pnlTop.Anchor = AnchorStyles.Left | AnchorStyles.Bottom;
Label lblTop = new Label();
lblTop.Parent = pnlTop;
lblTop.Text = "TopIndex: ";
xSize = ((int)(Font.Height * .5) * lblTop.Text.Length);
lblTop.Size = new Size(xSize, Font.Height + 10);
txtTop = new TextBox();
txtTop.Parent = pnlTop;
txtTop.Location = new Point(lblTop.Right, lblTop.Top);
txtTop.Text = lb.TopIndex.ToString();
txtTop.Size = new Size((int)(Font.Height * .75) * 3,
Font.Height + 10);
btnTop = new Button();
btnTop.Parent = pnlTop;
btnTop.Text = "Update";
btnTop.Location = new Point(txtTop.Right + 10, txtTop.Top);
btnTop.Click += new System.EventHandler(btnTop_Click);
lb.Items.Add("12345");
lb.Items.Add("67890");
lb.Items.Add("7890");
lb.Items.Add("890");
}
static void Main()
{
Application.Run(new ListBoxSelectionMode());
}
private void rdoMulti_CheckedChanged(object sender, EventArgs e)
{
RadioButton rdo = (RadioButton)sender;
lb.SelectionMode = (SelectionMode)rdo.Tag;
}
private void btnTop_Click(object sender, EventArgs e)
{
txtTop.Text = lb.TopIndex.ToString();
}
}</source>
