封装组合框时,如何将Items属性封装为强类型(自定义的类型)？

[DalyQiao]

在封装组合框时,遇到个麻烦,就是对Items属性没办法封装，没办法让他变成我的自定义集合类型。

有那位大侠能救我于水火之中？

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using Kingdee.Hk.Framework;
using System.Drawing.Design;
using System.Xml;
using System.Xml.XPath;

namespace Kingdee.Hk.Ui.Component.CBX
{
    /// <summary>
    /// 本组合框从数据库中查询数据,然后打包成项,填入组合框后供选择
    /// </summary>
    public partial class HkCbx_Sql : HkCbx_ 
    {
        public HkCbx_Sql()
        {
            InitializeComponent();
            base.Items.Clear();
            _Items = new HkDataItemCollection(this);
        }


        private string _KeyXmlElementName="";
        private string _ValueXmlElementName="";

        private string _Xml="";
        private string _XPath="";

        private string _SqlCommandText;
        private string _FixedFilter="";
        private string _Filter="";
        private string _DataTableFilter="";

        [Category ("业务-公共"), DisplayName ( "关键字元素名")]
        public string KeyXmlElementName
        {
            get { return _KeyXmlElementName; }
            set { _KeyXmlElementName = value; }
        }

        [Category("业务-公共"), DisplayName("值元素名")]
        public string ValueXmlElementName
        {
            get { return _ValueXmlElementName; }
            set { _ValueXmlElementName = value; }
        }

        [Category("业务-XML"), DisplayName("xml文档片断")]
        public string Xml
        {
            get { return _Xml; }
            set { _Xml = value; }
        }

        [Category("业务-XML"), DisplayName("过滤XPath表达式")]
        public string XPath
        {
            get { return _XPath; }
            set { _XPath = value; }
        }


        [Category("业务-数据库"), DisplayName("数据库命令")]
        public string SqlCommandText
        {
            get { return _SqlCommandText; }
            set { _SqlCommandText = value; }
        }

        [Category("业务-数据库"), DisplayName("固定的过滤器")]
        public string FixedFilter
        {
            get { return _FixedFilter; }
            set { _FixedFilter = value; }
        }

        [Category("业务-数据库"), DisplayName("变动过滤器")]
        public string Filter
        {
            get { return _Filter; }
            set { _Filter = value; }
        }

        [Category("业务-数据库"), DisplayName("结果集过滤器")]
        public string DataTableFilter
        {
            get { return _DataTableFilter; }
            set { _DataTableFilter = value; }
        }

        public string GetFullSqlCommandText()
        {
            StringBuilder sb = new StringBuilder(_SqlCommandText);
            sb.Replace("@@Filter@@", Filter);
            sb.Replace("@@FixedFilter@@", FixedFilter);
            return sb.ToString();
        }

        public void  RefreshFromDataSource ()
        {
            if (this.DesignMode == false)
            {
                this.Items.Clear();
                IDbCommandAdapter adp = GlobalObject.DbCommandAdapter;
                DataSet ds = adp.ExecuteSQL(this.GetFullSqlCommandText());
                XmlDataDocument doc = new XmlDataDocument(ds);

                DataRow[] rs = ds.Tables[0].Select(DataTableFilter);
                foreach (DataRow r in rs)
                {
                    XmlElement ele = doc.GetElementFromRow(r);

                    HkDataItem item = new HkDataItem ( this.KeyXmlElementName, this.ValueXmlElementName);
                    item.Xml = ele.OuterXml ;
                    this.Items.Add(item );
                    //base.Items.Add(item); //如果不加入这一行,在选择时就会出错,但加了之后,项目就重复了,因为本控件有了两个集合
                    ele = null;
                }
                doc = null;
                rs = null;
                ds.Dispose();
                adp.Dispose();

            }
        }


        public void RefreshFromXml()
        {
            if (this.DesignMode == false)
            {
                if (string.IsNullOrEmpty(this.XPath) == false || string.IsNullOrEmpty(this.Xml) == false)
                {
                    this.Items.Clear();
                    XmlDocument doc = new XmlDocument();
                    doc.LoadXml(this.Xml);
                    XmlNodeList nodes = doc.SelectNodes(string.Format("descendant::{0}", this.XPath));
                    foreach (XmlNode node in nodes)
                    {
                        this.Items.Add(this.KeyXmlElementName, this.ValueXmlElementName, node.OuterXml);
                    }
                }
            }
        }

        protected override void OnCreateControl()
        {
            base.OnCreateControl();
            if (string.IsNullOrEmpty(this.SqlCommandText) == false)
                this.RefreshFromDataSource();
            else
                this.RefreshFromXml();

            this.DropDownHeight = 200;

        }


        
        /// <summary>
        /// 覆盖原有的变量,重写一个
        /// </summary>
        protected HkDataItemCollection _Items;
        public new virtual HkDataItemCollection Items
        {
            get
            {
                return _Items;
            }
        }

        public override int SelectedIndex
        {
            get
            {
                return base.SelectedIndex;
            }
            set
            {
                base.SelectedIndex = value;
            }
        }

        public override
        //■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■
        [Editor(typeof(HkDataItemCollectionEditor), typeof(UITypeEditor))]
        public class HkDataItemCollection:ObjectCollection 
        {
            public HkDataItemCollection(HkCbx_Sql owner):base(owner )
            {

            }

            public int Add(string keyName, string valueName, string xml)
            {
                HkDataItem item = new HkDataItem(keyName, valueName);
                item.Xml = xml;
                return this.Add(item);
            }
            public new HkDataItem  this[int index]
            {
                get
                {
                    return (HkDataItem)(base[index]);
                }
                set
                {
                    base[index] = value;
                }
            }

            private string _KeyXmlElementName;

            public string KeyXmlElementName
            {
                get { return _KeyXmlElementName; }
                set 
                {
                    foreach (HkDataItem item in this)
                    {
                        item.KeyXmlElementName = value;
                    }
                    _KeyXmlElementName = value; 
                }
            }
            private string _ValueXmlElementName;

            public string ValueXmlElementName
            {
                get { return _ValueXmlElementName; }
                set 
                {
                    foreach (HkDataItem item in this)
                    {
                        item.ValueXmlElementName = value;
                    }
                    _ValueXmlElementName = value;
                }
            }


        }
    }
}

[-小蕾-]

帮顶，坐等高手。。

[shuzhan87]

自定义一个继承自item的类 将这个类加入组合框自定义类中