C#界面设计之ComboBox与ListBox的使用

同样先来效果图：

主要代码如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace ComboListBox
{
    public partial class Form1 : Form
    {
        public Form1( )
        {
            InitializeComponent( );
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            //设置cmbHouXuan只能从ComboBox中的已有候选值选择
            this.cmbHouXuan.DropDownStyle = ComboBoxStyle.DropDownList;
            //lstResult只能执行单选，并且对所有值进行排序
            this.lstResults.SelectionMode = SelectionMode.One;
            this.lstResults.Sorted = true;
            this.GenerateCombItems( );          //产生ComboBox中的可选项
        }

        private void GenerateCombItems( )
        {
            this.cmbHouXuan.Items.Clear( );     //移除原有的数据
            Random rd = new Random();
            for (int i = 0; i < 10; i++)        //随机生成10个新的数据
            {
                string item = string.Format("Item-{0:X8}", rd.Next( ));
                this.cmbHouXuan.Items.Add(item);   //添加到ComboBox中
            }
            this.cmbHouXuan.SelectedIndex = 0;      //默认选中第一条
        }
        //重新生成ComboBox中的侯选项
        private void btnFresh_Click(object sender, EventArgs e)
        {
            this.GenerateCombItems( );      //重新生成CombBox中的候选项
        }
        //将CombBox中选中的值添加到ListBox中
        private void btnAddOne_Click(object sender, EventArgs e)
        {
            //通过ComboBox.SelectedItem获取当前选中的候选项，然后添加到ListBox中
            string item = (string)this.cmbHouXuan.SelectedItem;     
            this.lstResults.Items.Add(item);
        }
        //从ListBox中移除当前选中项
        private void btnRemoveOne_Click(object sender, EventArgs e)
        {
            if (this.lstResults.SelectedIndex >= 0)     //如果当前ListBox中有选中条目，移除它
            {
                this.lstResults.Items.RemoveAt(this.lstResults.SelectedIndex);
            }
        }
        //从ListBox中移除所有项
        private void btnRemovAll_Click(object sender, EventArgs e)
        {
            this.lstResults.Items.Clear( );
        }
    }
}

控件的标注信息代码如下：

namespace ComboListBox
{
    partial class Form1
    {
        /// <summary>
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// 清理所有正在使用的资源。
        /// </summary>
        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose( );
            }
            base.Dispose(disposing);
        }

        #region Windows 窗体设计器生成的代码

        /// <summary>
        /// 设计器支持所需的方法 - 不要
        /// 使用代码编辑器修改此方法的内容。
        /// </summary>
        private void InitializeComponent( )
        {
            this.cmbHouXuan = new System.Windows.Forms.ComboBox( );
            this.lstResults = new System.Windows.Forms.ListBox( );
            this.label1 = new System.Windows.Forms.Label( );
            this.btnFresh = new System.Windows.Forms.Button( );
            this.btnAddOne = new System.Windows.Forms.Button( );
            this.btnRemoveOne = new System.Windows.Forms.Button( );
            this.btnRemovAll = new System.Windows.Forms.Button( );
            this.SuspendLayout( );
            // 
            // cmbHouXuan
            // 
            this.cmbHouXuan.FormattingEnabled = true;
            this.cmbHouXuan.Location = new System.Drawing.Point(19, 44);
            this.cmbHouXuan.Name = "cmbHouXuan";
            this.cmbHouXuan.Size = new System.Drawing.Size(159, 20);
            this.cmbHouXuan.TabIndex = 0;
            // 
            // lstResults
            // 
            this.lstResults.FormattingEnabled = true;
            this.lstResults.ItemHeight = 12;
            this.lstResults.Location = new System.Drawing.Point(217, 12);
            this.lstResults.Name = "lstResults";
            this.lstResults.Size = new System.Drawing.Size(222, 352);
            this.lstResults.TabIndex = 1;
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(22, 27);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(41, 12);
            this.label1.TabIndex = 2;
            this.label1.Text = "候选项";
            // 
            // btnFresh
            // 
            this.btnFresh.Location = new System.Drawing.Point(40, 70);
            this.btnFresh.Name = "btnFresh";
            this.btnFresh.Size = new System.Drawing.Size(113, 35);
            this.btnFresh.TabIndex = 3;
            this.btnFresh.Text = "刷新候选项";
            this.btnFresh.UseVisualStyleBackColor = true;
            this.btnFresh.Click += new System.EventHandler(this.btnFresh_Click);
            // 
            // btnAddOne
            // 
            this.btnAddOne.Location = new System.Drawing.Point(40, 166);
            this.btnAddOne.Name = "btnAddOne";
            this.btnAddOne.Size = new System.Drawing.Size(113, 35);
            this.btnAddOne.TabIndex = 3;
            this.btnAddOne.Text = "添加到列表==>";
            this.btnAddOne.UseVisualStyleBackColor = true;
            this.btnAddOne.Click += new System.EventHandler(this.btnAddOne_Click);
            // 
            // btnRemoveOne
            // 
            this.btnRemoveOne.Location = new System.Drawing.Point(40, 229);
            this.btnRemoveOne.Name = "btnRemoveOne";
            this.btnRemoveOne.Size = new System.Drawing.Size(113, 35);
            this.btnRemoveOne.TabIndex = 3;
            this.btnRemoveOne.Text = "<==从列表移除";
            this.btnRemoveOne.UseVisualStyleBackColor = true;
            this.btnRemoveOne.Click += new System.EventHandler(this.btnRemoveOne_Click);
            // 
            // btnRemovAll
            // 
            this.btnRemovAll.Location = new System.Drawing.Point(40, 301);
            this.btnRemovAll.Name = "btnRemovAll";
            this.btnRemovAll.Size = new System.Drawing.Size(113, 35);
            this.btnRemovAll.TabIndex = 3;
            this.btnRemovAll.Text = "<<<==全部移除";
            this.btnRemovAll.UseVisualStyleBackColor = true;
            this.btnRemovAll.Click += new System.EventHandler(this.btnRemovAll_Click);
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(468, 382);
            this.Controls.Add(this.btnRemovAll);
            this.Controls.Add(this.btnRemoveOne);
            this.Controls.Add(this.btnAddOne);
            this.Controls.Add(this.btnFresh);
            this.Controls.Add(this.label1);
            this.Controls.Add(this.lstResults);
            this.Controls.Add(this.cmbHouXuan);
            this.Name = "Form1";
            this.Text = "ComboBox和ListBox实例";
            this.Load += new System.EventHandler(this.Form1_Load);
            this.ResumeLayout(false);
            this.PerformLayout( );

        }

        #endregion

        private System.Windows.Forms.ComboBox cmbHouXuan;
        private System.Windows.Forms.ListBox lstResults;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.Button btnFresh;
        private System.Windows.Forms.Button btnAddOne;
        private System.Windows.Forms.Button btnRemoveOne;
        private System.Windows.Forms.Button btnRemovAll;
    }
}