[C#] ComboBox의 DataSource에 DataTable을 연결하여 사용하기

1. 사용 예제

[그림1 콤보박스 화면에 표시될 속성명 지정하기

private void SetCbTest()
{
    Cursor.Current = Cursors.WaitCursor;

    var rd = new Random();
    var dt = new DataTable();
    var col = dt.Columns.Add("CHK");
    col = dt.Columns.Add("IDX");
    col = dt.Columns.Add("NM");
    for (int i = 0; i < 1000; ++i)
    {
        var row = dt.Rows.Add();
        row["CHK"] = rd.Next(1, 1000) % 2 == 0;
        row["IDX"] = i.ToString();
        row["NM"] = $"Name{i}";
    }
    cbTest.DataSource = dt;
    cbTest.DisplayMember = TxbDisplayMember.Text;

    Cursor.Current = Cursors.Default;
}

 

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2. 컨트롤 소스
        /// <summary>
        /// 생성자
        /// </summary>
        public CjComboBox()
        {
            InitializeComponent();
        }

        /// <summary>
        /// 현재 선택된 아이템 (형식:object[])
        /// </summary>
        public object[] SelectedObjects
        {
            get
            {
                if (this.SelectedIndex < 0)
                    return null;

                return this[this.SelectedIndex];
            }
        }

        /// <summary>
        /// Indexer 재정의하기
        /// </summary>
        /// <param name="i">인덱스 (zero-based)</param>
        /// <returns>배열</returns>
        public object[] this[int i]
        {
            get
            {
                try
                {
                    if (i < 0 || i >= this.Items.Count)
                        return null;

                    if (this.Items[i] == null || !(this.Items[i] is DataRowView))
                    {
                        return null;
                    }

                    return (this.Items[i] as DataRowView).Row.ItemArray;
                }
                catch (Exception ex)
                {
                    Debug.WriteLine($"{this.Name} Error : {ex}");
                }

                return null;
            }
            set
            {
                try
                {
                    if (this.DataSource != null && this.DataSource is DataTable)
                    {
                        DataTable dt = this.DataSource as DataTable;
                        if (0 <= i && i < dt.Rows.Count)
                        {
                            dt.Rows[i].ItemArray = value;
                        }
                    }
                }
                catch (Exception ex)
                {
                    Debug.WriteLine($"{this.Name} Error : {ex}");
                }
            }
        }

        /// <summary>
        /// Indexer 재정의하기
        /// </summary>
        /// <param name="i">인덱스 (zero-based)</param>
        /// <param name="fieldName">필드명</param>
        /// <returns>필드값</returns>
        public object this[int i, string fieldName]
        {
            get
            {
                try
                {
                    if (i < 0 || i >= this.Items.Count)
                        return null;

                    if (this.Items[i] == null || !(this.Items[i] is DataRowView))
                    {
                        Debug.WriteLine($"{this.Name}의 DataSource가 DataTable 형식이 아닙니다.");
                        return null;
                    }

                    DataRow dr = (this.Items[i] as DataRowView).Row;
                    if (dr.Table.Columns.Contains(fieldName))
                        return dr[fieldName];
                    else
                    {
                        Debug.WriteLine($"{this.Name}에는 {fieldName} 속성이 없습니다.");
                        return null;
                    }
                }
                catch (Exception ex)
                {
                    Debug.WriteLine($"{this.Name} Error : {ex}");
                }

                return null;
            }
        }
    }