combobox 中文首字母检索功能

r囧r小猫 2022-08-27 04:49 149阅读 0赞

using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Windows.Forms;
    using System.Collections;
    
    namespace PYFilter
    {
        class ComboBoxEx :ComboBox
        {
            private ArrayList m_list = new ArrayList();
            protected override void OnEnter(EventArgs e)
            {
                m_list.Clear();
                m_list.AddRange(this.Items);
                base.OnEnter(e);
            }
            protected override void OnLeave(EventArgs e)
            {
                this.Items.Clear();
                this.Items.AddRange(m_list.ToArray());
                base.OnLeave(e);
            }
            protected override void OnTextUpdate(EventArgs e)
            {
                while (this.Items.Count > 0)
                {
                    this.Items.RemoveAt(0);
                }
                foreach (object o in this.m_list)
                {
                    if ( GetChineseSpell(o.ToString()).ToLower().Contains(this.Text.ToLower()))
                    {
                        this.Items.Add(o);
                    }
                }
                this.DroppedDown = true;
                this.Cursor = Cursors.Default;
                base.OnTextUpdate(e);
            }
            static public string GetChineseSpell(string strText)
            {
                int len = strText.Length;
                string myStr = "";
                for (int i = 0; i < len; i++)
                {
                    myStr += getSpell(strText.Substring(i, 1));
                }
                return myStr;
            }
            static public string getSpell(string cnChar)
            {
                byte[] arrCN = Encoding.Default.GetBytes(cnChar);
                if (arrCN.Length > 1)
                {
                    int area = (short)arrCN[0];
                    int pos = (short)arrCN[1];
                    int code = (area << 8) + pos;
                    int[] areacode = { 45217, 45253, 45761, 46318, 46826, 47010, 47297, 47614, 48119, 48119, 49062, 49324, 49896, 50371, 50614, 50622, 50906, 51387, 51446, 52218, 52698, 52698, 52698, 52980, 53689, 54481 };
                    for (int i = 0; i < 26; i++)
                    {
                        int max = 55290;
                        if (i != 25) max = areacode[i + 1];
                        if (areacode[i] <= code && code < max)
                        {
                            return Encoding.Default.GetString(new byte[] { (byte)(65 + i) });
                        }
                    }
                    return "*";
                }
                else 
                    return cnChar;
            }
        }
    }