Use a ComboBox instead of a TextBox. The following example will autocomplete, matching any piece of the text, not just the starting letters.
This should be a complete form, just add your own data source, and data source column names. :-)
using System;
using System.Data;
using System.Windows.Forms;
public partial class frmTestAutocomplete : Form
{
private DataTable maoCompleteList;
private const string MC_DISPLAY_COL = "name";
private const string MC_ID_COL = "id";
public frmTestAutocomplete()
{
InitializeComponent();
}
private void frmTestAutocomplete_Load(object sender, EventArgs e)
{
maoCompleteList = GetDataTableFromDatabase();
maoCompleteList.CaseSensitive = false; //turn off case sensitivity for searching
testCombo.DisplayMember = MC_DISPLAY_COL;
testCombo.ValueMember = MC_ID_COL;
testCombo.DataSource = maoCompleteList;
testCombo.SelectedIndexChanged += testCombo_SelectedIndexChanged;
testCombo.KeyUp += testCombo_KeyUp;
}
private void testCombo_KeyUp(object sender, KeyEventArgs e)
{
//use keyUp event, as text changed traps too many other evengts.
ComboBox oBox = (ComboBox)sender;
string sBoxText = oBox.Text;
DataRow[] oFilteredRows = maoCompleteList.Select(MC_DISPLAY_COL + " Like '%" + sBoxText + "%'");
DataTable oFilteredDT = oFilteredRows.Length > 0
? oFilteredRows.CopyToDataTable()
: maoCompleteList;
//NOW THAT WE HAVE OUR FILTERED LIST, WE NEED TO RE-BIND IT WIHOUT CHANGING THE TEXT IN THE ComboBox.
//1).UNREGISTER THE SELECTED EVENT BEFORE RE-BINDING, b/c IT TRIGGERS ON BIND.
oBox.SelectedIndexChanged -= testCombo_SelectedIndexChanged; //don't select on typing.
oBox.DataSource = oFilteredDT; //2).rebind to filtered list.
oBox.SelectedIndexChanged += testCombo_SelectedIndexChanged;
//3).show the user the new filtered list.
oBox.DroppedDown = true; //this will overwrite the text in the ComboBox, so 4&5 put it back.
//4).binding data source erases text, so now we need to put the user's text back,
oBox.Text = sBoxText;
oBox.SelectionStart = sBoxText.Length; //5). need to put the user's cursor back where it was.
}
private void testCombo_SelectedIndexChanged(object sender, EventArgs e)
{
ComboBox oBox = (ComboBox)sender;
if (oBox.SelectedValue != null)
{
MessageBox.Show(string.Format(@"Item #{0} was selected.", oBox.SelectedValue));
}
}
}
//=====================================================================================================
// code from frmTestAutocomplete.Designer.cs
//=====================================================================================================
partial class frmTestAutocomplete
{
/// <summary>
/// Required designer variable.
/// </summary>
private readonly 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.testCombo = new System.Windows.Forms.ComboBox();
this.SuspendLayout();
//
// testCombo
//
this.testCombo.FormattingEnabled = true;
this.testCombo.Location = new System.Drawing.Point(27, 51);
this.testCombo.Name = "testCombo";
this.testCombo.Size = new System.Drawing.Size(224, 21);
this.testCombo.TabIndex = 0;
//
// frmTestAutocomplete
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(292, 273);
this.Controls.Add(this.testCombo);
this.Name = "frmTestAutocomplete";
this.Text = "frmTestAutocomplete";
this.Load += new System.EventHandler(this.frmTestAutocomplete_Load);
this.ResumeLayout(false);
}
#endregion
private System.Windows.Forms.ComboBox testCombo;
}
