WindowForm下拉控件显示网格列表

描述：

ComboBox和DataGridView两个控件制作复合控件，使用WindowForm自带控件显示详细下拉列表信息项！

用最少的代码量去实现ComBoxDataGridView代码下拉框。

效果图：

代码类：

public class ComboBoxDataGridView : ComboBox
    {
        //系统消息消息中的鼠标点击
        private const int WINDOW_MSG_BUTTONDOWN = 0x201;
        // 系统消息消息中的鼠标按下事件
        private const int WINDOW_MSG_BUTTONDBCLICK = 0x203;
        //存放自定义控件或 Windows 窗体控件。
        private ToolStripControlHost hostDataGridView;
        //Menu类似menu的容器
        private ToolStripDropDown dropDown;


        private int dropDownViewWidth = 0;
        /// <summary>
        /// 下拉列表的宽度
        /// 如果如果不设置此属性：默认this.Width;
        /// </summary>
        public int DropDownViewWidth
        {
            set { dropDownViewWidth = value; }
            get
            {
                return dropDownViewWidth == 0 ? this.Width : dropDownViewWidth;
            }
        }
        /// <summary>
        /// 构造函数（默认是空的网格）
        /// </summary>
        public ComboBoxDataGridView()
        {
            DataGridView dataGridView = new DataGridView();
            InitControlView(dataGridView);
        }
        /// <summary>
        /// 初始化树下拉框
        /// </summary>
        /// <param name="innerView">DataGridView</param>
        public void InitControlView(DataGridView innerView)
        {
            if (null != innerView)
            {
                innerView.DoubleClick += InnerView_DoubleClick;
                innerView.BorderStyle = BorderStyle.None;
                innerView.Dock = DockStyle.Fill;
                hostDataGridView = new ToolStripControlHost(innerView);
                dropDown = new ToolStripDropDown();
                dropDown.Width = DropDownViewWidth;
                dropDown.Items.Clear();
                dropDown.Items.Add(hostDataGridView);
            }
        }
        /// <summary>
        /// 网格控件双击选择条目后触发选择
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void InnerView_DoubleClick(object sender, EventArgs e)
        {
            if (DataView.CurrentRow == null)
                return;
            this.Items.Clear();
            this.Items.Add(DataView.CurrentRow);
            this.Text = DataView.CurrentRow.Cells[GetColumnNameByDataPropertyName(this.DisplayMember)].Value.ToString();
            this.Name = DataView.CurrentRow.Cells[GetColumnNameByDataPropertyName(this.DisplayMember)].Value.ToString();
            this.Tag = DataView.CurrentRow.Cells[GetColumnNameByDataPropertyName(this.ValueMember)].Value.ToString();
            this.Focus();
            dropDown.Close();
        }
        /// <summary>
        /// 根据数据源属性获取列名
        /// </summary>
        /// <param name="dataPropertyName">数据源属性：DisplayMember和ValueMember</param>
        /// <returns></returns>
        protected string GetColumnNameByDataPropertyName(string dataPropertyName)
        {
            foreach (DataGridViewColumn column in this.DataView.Columns)
            {
                if (column.DataPropertyName == dataPropertyName)
                    return column.Name;
            }
            return string.Empty;
        }


        /// <summary>
        /// 设置选中的行：能区分唯一条目标识信息
        /// </summary>
        /// <param name="columnName">列名</param>
        /// <param name="value">值：主键</param>
        public void SetCurSelected(string dataPropertyName, object value)
        {
            foreach (DataGridViewRow row in this.DataView.Rows)
            {
                if (row.Cells[GetColumnNameByDataPropertyName(dataPropertyName)].Value == value)
                {
                    //this.DataView.CurrentCell = DataView.Rows[row.Index].Cells[columnName];
                    row.Selected = true;
                    break;
                }
            }
            this.Items.Clear();
            this.Items.Add(DataView.CurrentRow);
            this.SelectedIndex = 0;
            this.Name = DataView.CurrentRow.Cells[GetColumnNameByDataPropertyName(this.DisplayMember)].Value.ToString();
            this.Tag = DataView.CurrentRow.Cells[GetColumnNameByDataPropertyName(this.ValueMember)].Value.ToString();
        }

        /// <summary>
        /// 获取控件内的DataGridView
        /// </summary>
        public DataGridView DataView
        {
            get { return hostDataGridView.Control as DataGridView; }
        }
        /// <summary>
        /// 显示网格列表
        /// </summary>
        private void ShowDropDown()
        {
            if (dropDown != null)
            {
                hostDataGridView.Size = new Size(this.DropDownViewWidth - 2, DropDownHeight);
                dropDown.Show(this, 0, this.Height);
            }
        }

        /// <summary>
        /// 处理系统消息（此处是指点击combbox时弹出下拉框）
        /// </summary>
        /// <param name="m"></param>
        protected override void WndProc(ref Message m)
        {
            if (m.Msg == WINDOW_MSG_BUTTONDBCLICK || m.Msg == WINDOW_MSG_BUTTONDOWN)
            {
                ShowDropDown();
                return;
            }
            base.WndProc(ref m);
        }

        /// <summary>
        /// 释放内存：dropDown
        /// </summary>
        /// <param name="disposing"></param>
        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                if (dropDown != null)
                {
                    dropDown.Dispose();
                    dropDown = null;
                }
            }
            base.Dispose(disposing);
        }
    }

调用方法：

            //将ComboBoxDataGridView自定义控件拖放到WindowForm窗体上后，
            //并且将DataGridView控件也拖放一个
            List<object> lst = new List<object>();
            lst.Add(new { Code = "1", Name = "姓名" });
            lst.Add(new { Code = "2", Name = "性别" });
            lst.Add(new { Code = "3", Name = "年龄" });
            comboBoxDataGridView1.DisplayMember = "Name";
            comboBoxDataGridView1.ValueMember = "Code";
            this.dataGridView1.DataSource = lst;
            this.Controls.Remove(this.dataGridView1);
            comboBoxDataGridView1.InitControlView(this.dataGridView1);
            this.dataGridView1.Refresh();

如果我们需要以检索的方式去实现过滤下拉网格出现的列表，可以增加设置触发KeyDown事件实现过滤显示功能，此处不在过多说明！