Form1.cs

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace SetComboBoxValue {
    /// <summary>
    /// Summary description for Form1.
    /// </summary>
    public class Form1 : System.Windows.Forms.Form {
        private DevExpress.XtraEditors.ComboBoxEdit comboBoxEdit1;
        private DevExpress.XtraEditors.SimpleButton simpleButton1;
        private DevExpress.XtraGrid.GridControl gridControl1;
        private DevExpress.XtraGrid.Views.Grid.GridView gridView1;
        private DevExpress.XtraBars.BarManager barManager1;
        private DevExpress.XtraBars.BarDockControl barDockControlTop;
        private DevExpress.XtraBars.BarDockControl barDockControlBottom;
        private DevExpress.XtraBars.BarDockControl barDockControlLeft;
        private DevExpress.XtraBars.BarDockControl barDockControlRight;
        private DevExpress.XtraBars.Bar bar1;
        private DevExpress.XtraEditors.Repository.PersistentRepository persistentRepository1;
        private DevExpress.XtraEditors.Repository.RepositoryItemComboBox repositoryItemComboBox1;
        private System.Data.DataSet dataSet1;
        private System.Data.DataTable dataTable1;
        private System.Data.DataColumn dataColumn1;
        private DevExpress.XtraGrid.Columns.GridColumn colDay;
        private DevExpress.XtraBars.BarEditItem barEditItem1;
        private DevExpress.XtraEditors.SimpleButton simpleButton2;
        private BindingSource bindingSource1;
        private System.ComponentModel.IContainer components;

        public Form1() {
            //
            // Required for Windows Form Designer support
            //
            InitializeComponent();

            //
            // TODO: Add any constructor code after InitializeComponent call
            //
        }

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        protected override void Dispose(bool disposing) {
            if(disposing) {
                if(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.components = new System.ComponentModel.Container();
            this.comboBoxEdit1 = new DevExpress.XtraEditors.ComboBoxEdit();
            this.simpleButton1 = new DevExpress.XtraEditors.SimpleButton();
            this.gridControl1 = new DevExpress.XtraGrid.GridControl();
            this.dataTable1 = new System.Data.DataTable();
            this.dataColumn1 = new System.Data.DataColumn();
            this.persistentRepository1 = new DevExpress.XtraEditors.Repository.PersistentRepository(this.components);
            this.repositoryItemComboBox1 = new DevExpress.XtraEditors.Repository.RepositoryItemComboBox();
            this.gridView1 = new DevExpress.XtraGrid.Views.Grid.GridView();
            this.colDay = new DevExpress.XtraGrid.Columns.GridColumn();
            this.barManager1 = new DevExpress.XtraBars.BarManager(this.components);
            this.bar1 = new DevExpress.XtraBars.Bar();
            this.barEditItem1 = new DevExpress.XtraBars.BarEditItem();
            this.barDockControlTop = new DevExpress.XtraBars.BarDockControl();
            this.barDockControlBottom = new DevExpress.XtraBars.BarDockControl();
            this.barDockControlLeft = new DevExpress.XtraBars.BarDockControl();
            this.barDockControlRight = new DevExpress.XtraBars.BarDockControl();
            this.dataSet1 = new System.Data.DataSet();
            this.simpleButton2 = new DevExpress.XtraEditors.SimpleButton();
            this.bindingSource1 = new System.Windows.Forms.BindingSource(this.components);
            ((System.ComponentModel.ISupportInitialize)(this.comboBoxEdit1.Properties)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.gridControl1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.dataTable1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.repositoryItemComboBox1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.gridView1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.barManager1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.dataSet1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.bindingSource1)).BeginInit();
            this.SuspendLayout();
            // 
            // comboBoxEdit1
            // 
            this.comboBoxEdit1.Location = new System.Drawing.Point(8, 32);
            this.comboBoxEdit1.Name = "comboBoxEdit1";
            this.comboBoxEdit1.Properties.Buttons.AddRange(new DevExpress.XtraEditors.Controls.EditorButton[] {
            new DevExpress.XtraEditors.Controls.EditorButton(DevExpress.XtraEditors.Controls.ButtonPredefines.Combo)});
            this.comboBoxEdit1.Size = new System.Drawing.Size(208, 20);
            this.comboBoxEdit1.TabIndex = 0;
            // 
            // simpleButton1
            // 
            this.simpleButton1.Location = new System.Drawing.Point(367, 32);
            this.simpleButton1.Name = "simpleButton1";
            this.simpleButton1.Size = new System.Drawing.Size(168, 23);
            this.simpleButton1.TabIndex = 1;
            this.simpleButton1.Text = "Set Day Index 1";
            this.simpleButton1.Click += new System.EventHandler(this.simpleButton1_Click);
            // 
            // gridControl1
            // 
            this.gridControl1.DataSource = this.bindingSource1;
            this.gridControl1.ExternalRepository = this.persistentRepository1;
            this.gridControl1.Location = new System.Drawing.Point(8, 64);
            this.gridControl1.MainView = this.gridView1;
            this.gridControl1.Name = "gridControl1";
            this.gridControl1.Size = new System.Drawing.Size(325, 208);
            this.gridControl1.TabIndex = 2;
            this.gridControl1.ViewCollection.AddRange(new DevExpress.XtraGrid.Views.Base.BaseView[] {
            this.gridView1});
            // 
            // dataTable1
            // 
            this.dataTable1.Columns.AddRange(new System.Data.DataColumn[] {
            this.dataColumn1});
            this.dataTable1.TableName = "Table1";
            // 
            // dataColumn1
            // 
            this.dataColumn1.ColumnName = "Day";
            // 
            // persistentRepository1
            // 
            this.persistentRepository1.Items.AddRange(new DevExpress.XtraEditors.Repository.RepositoryItem[] {
            this.repositoryItemComboBox1});
            // 
            // repositoryItemComboBox1
            // 
            this.repositoryItemComboBox1.Buttons.AddRange(new DevExpress.XtraEditors.Controls.EditorButton[] {
            new DevExpress.XtraEditors.Controls.EditorButton(DevExpress.XtraEditors.Controls.ButtonPredefines.Combo)});
            this.repositoryItemComboBox1.Items.AddRange(new object[] {
            "Sunday",
            "Monday",
            "Tuesday",
            "Wednesday",
            "Thursday",
            "Friday",
            "Saturday"});
            this.repositoryItemComboBox1.Name = "repositoryItemComboBox1";
            this.repositoryItemComboBox1.TextEditStyle = DevExpress.XtraEditors.Controls.TextEditStyles.DisableTextEditor;
            // 
            // gridView1
            // 
            this.gridView1.Columns.AddRange(new DevExpress.XtraGrid.Columns.GridColumn[] {
            this.colDay});
            this.gridView1.GridControl = this.gridControl1;
            this.gridView1.Name = "gridView1";
            // 
            // colDay
            // 
            this.colDay.Caption = "Day";
            this.colDay.ColumnEdit = this.repositoryItemComboBox1;
            this.colDay.FieldName = "Day";
            this.colDay.Name = "colDay";
            this.colDay.Visible = true;
            this.colDay.VisibleIndex = 0;
            // 
            // barManager1
            // 
            this.barManager1.Bars.AddRange(new DevExpress.XtraBars.Bar[] {
            this.bar1});
            this.barManager1.DockControls.Add(this.barDockControlTop);
            this.barManager1.DockControls.Add(this.barDockControlBottom);
            this.barManager1.DockControls.Add(this.barDockControlLeft);
            this.barManager1.DockControls.Add(this.barDockControlRight);
            this.barManager1.ExternalRepository = this.persistentRepository1;
            this.barManager1.Form = this;
            this.barManager1.Items.AddRange(new DevExpress.XtraBars.BarItem[] {
            this.barEditItem1});
            this.barManager1.MaxItemId = 2;
            // 
            // bar1
            // 
            this.bar1.BarName = "Custom 1";
            this.bar1.DockCol = 0;
            this.bar1.DockRow = 0;
            this.bar1.DockStyle = DevExpress.XtraBars.BarDockStyle.Top;
            this.bar1.LinksPersistInfo.AddRange(new DevExpress.XtraBars.LinkPersistInfo[] {
            new DevExpress.XtraBars.LinkPersistInfo(DevExpress.XtraBars.BarLinkUserDefines.Width, this.barEditItem1, "", false, true, true, 201)});
            this.bar1.Text = "Custom 1";
            // 
            // barEditItem1
            // 
            this.barEditItem1.Caption = "barEditItem1";
            this.barEditItem1.Edit = this.repositoryItemComboBox1;
            this.barEditItem1.Id = 0;
            this.barEditItem1.Name = "barEditItem1";
            // 
            // dataSet1
            // 
            this.dataSet1.DataSetName = "NewDataSet";
            this.dataSet1.Locale = new System.Globalization.CultureInfo("en-US");
            this.dataSet1.Tables.AddRange(new System.Data.DataTable[] {
            this.dataTable1});
            // 
            // simpleButton2
            // 
            this.simpleButton2.Location = new System.Drawing.Point(367, 61);
            this.simpleButton2.Name = "simpleButton2";
            this.simpleButton2.Size = new System.Drawing.Size(168, 23);
            this.simpleButton2.TabIndex = 1;
            this.simpleButton2.Text = "Get Selected Day and Index";
            this.simpleButton2.Click += new System.EventHandler(this.simpleButton2_Click);
            // 
            // bindingSource1
            // 
            this.bindingSource1.DataMember = "Table1";
            this.bindingSource1.DataSource = this.dataSet1;
            // 
            // Form1
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(545, 280);
            this.Controls.Add(this.gridControl1);
            this.Controls.Add(this.simpleButton2);
            this.Controls.Add(this.simpleButton1);
            this.Controls.Add(this.comboBoxEdit1);
            this.Controls.Add(this.barDockControlLeft);
            this.Controls.Add(this.barDockControlRight);
            this.Controls.Add(this.barDockControlBottom);
            this.Controls.Add(this.barDockControlTop);
            this.Name = "Form1";
            this.Text = "Form1";
            this.Load += new System.EventHandler(this.Form1_Load);
            ((System.ComponentModel.ISupportInitialize)(this.comboBoxEdit1.Properties)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.gridControl1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.dataTable1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.repositoryItemComboBox1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.gridView1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.barManager1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.dataSet1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.bindingSource1)).EndInit();
            this.ResumeLayout(false);

        }
        #endregion

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main() {
            Application.Run(new Form1());
        }

        private void Form1_Load(object sender, System.EventArgs e) {
            dataTable1.Rows.Add(new object[] { "Friday" });
            dataTable1.Rows.Add(new object[] { "Saturday" });

            comboBoxEdit1.Properties.Assign(repositoryItemComboBox1);
            gridControl1.RepositoryItems.Add(repositoryItemComboBox1);
        }

        private void simpleButton1_Click(object sender, System.EventArgs e) {
            // Get the value at index 1
            const int index = 1;
            object val = repositoryItemComboBox1.Items[index];

            // stand-alone editor
            //comboBoxEdit1.SelectedIndex = index;
            // or
            comboBoxEdit1.EditValue = val;

            // XtraGrid
            gridView1.SetRowCellValue(gridView1.FocusedRowHandle, "Day", val);

            // XtraBars
            barEditItem1.EditValue = val;
        }

        private void simpleButton2_Click(object sender, EventArgs e) {
            string result = "";
            object val;

            // XtraBars
            val = barEditItem1.EditValue;
            result += string.Format("XtraBars editor: \t {0} / {1}", val, repositoryItemComboBox1.Items.IndexOf(val));

            // stand-alone editor
            val = comboBoxEdit1.EditValue;
            result += string.Format("\nComboBoxEdit: \t {0} / {1}", val, repositoryItemComboBox1.Items.IndexOf(val));

            // XtraGrid
            val = gridView1.GetRowCellValue(gridView1.FocusedRowHandle, "Day");
            result += string.Format("\nXtraGrid cell: \t {0} / {1}", val, repositoryItemComboBox1.Items.IndexOf(val));

            MessageBox.Show(result);
        }
    }
}