using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows.Forms;using DevExpress.XtraEditors;namespace WindowsFormsApplication7{    public partial class Form1 : Form    {        public Form1()        {            InitializeComponent();        }        private void Form1_Load(object sender, EventArgs e)        {            lookUpEdit1.Properties.DisplayMember = "ID";            lookUpEdit1.Properties.ValueMember = "Names";            lookUpEdit1.Properties.DataSource = InitData();            lookUpEdit1.Properties.NullText = "请输入";            lookUpEdit1.Properties.PopulateColumns();            lookUpEdit1.Properties.BestFitMode = DevExpress.XtraEditors.Controls.BestFitMode.BestFitResizePopup;            //  lookUpEdit1.Properties.ImmediatePopup = true;            lookUpEdit1.ItemIndex = -1;            lookUpEdit1.Properties.Columns[0].Caption = "ID 号码";            lookUpEdit1.Properties.Columns[1].Caption = "姓名";            lookUpEdit1.Properties.Columns[1].Width = 120;            lookUpEdit1.Properties.Columns[2].Width = 300;            lookUpEdit1.Properties.Columns[2].Alignment = DevExpress.Utils.HorzAlignment.Center;            // lookUpEdit1.Properties.Columns[2].            //控制选择项的总宽度            lookUpEdit1.Properties.PopupWidth = 500;        }        private List<per> InitData()        {            List<per> list = new List<per>();            list.AddRange(new per[] { new per("12", "zwj1"), new per("123", "zwj33"), new per("12345", "z4wj3"), new per("123456", "zwj3123") });            return list;        }        private void lookUpEdit1_EditValueChanging(object sender, DevExpress.XtraEditors.Controls.ChangingEventArgs e)        {        }        private void lookUpEdit1_EditValueChanged(object sender, EventArgs e)        {            this.Text = (sender as LookUpEdit).Text;            this.Text += "*******" + lookUpEdit1.Text + "--" + lookUpEdit1.EditValue;        }    }    public class per    {        public per(string id, string names)        {            this.ID = id;            this.Names = names;        }        public string ID { get; set; }        public string Names { get; set; }    }}