C# Winfom 中ListBox的简单用法详解

this.listBox1.Items.Add("张晓东");

//检查添加值是否添加过
if(this.listBox1.items.Contains("张晓东")){
  MessageBox.show("集合成员已添加过！");  
}
else{
   //执行添加集合成员
}

//判断所有选中项集合大于0
if(this.listBox1.SelectedItems.Count > 0){
   //获取选中的值
   this.listBox1.SelectedItem.ToString(); 
}
else{
  MessageBox.Show("未选中listbox集合的值"); 
}

//移除listBox集合的项
this.listBox1.Items.Remove("张晓东");

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

namespace WindowsForms
{
  public partial class Form3 : Form
  {
    public Form3()
    {
      InitializeComponent();
    }

    /// <summary>
    /// 添加人员到采购部门
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void btnInsert_Click(object sender, EventArgs e)
    {
      //获取添加人的值
      string peopleText = this.txtPeople.Text.Trim().ToString();
      //获取listbox1的对象
      ListBox list1 = this.listBox1;
      //判断人员是否已经添加过
      if (!list1.Items.Contains(peopleText))
      {
        list1.Items.Add(peopleText);
      }
      else {
        MessageBox.Show("该人员已经添加过，无法重复添加！");
      }
    }

    /// <summary>
    /// 将采购人员转移到销售部门
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void btnRightMove_Click(object sender, EventArgs e)
    {
      //获取listbox1的所有选中的项
      if (this.listBox1.SelectedItems.Count > 0)
      {
        string checkPeople = this.listBox1.SelectedItem.ToString();
        //判断是否添加到listbox2
        if (!this.listBox2.Items.Contains(checkPeople)) {
          //添加人员到listbox2中
          this.listBox2.Items.Add(checkPeople);
          //移除listbox1中
          this.listBox1.Items.Remove(checkPeople);
        }
        else
        {
          MessageBox.Show("该人员已经转移过，无法重复转移！");
        }

      }
      else {
        MessageBox.Show("未选中采购人员，无法转移销售部门！");
      }
    }

    /// <summary>
    /// 将销售人员转移到采购部门
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    private void btnLeftMove_Click(object sender, EventArgs e)
    {
      //获取listbox2的所有选中的项
      if (this.listBox2.SelectedItems.Count > 0)
      {
        string checkPeople = this.listBox2.SelectedItem.ToString();
        //判断是否添加到listbox1
        if (!this.listBox1.Items.Contains(checkPeople))
        {
          //添加人员到listbox1中
          this.listBox1.Items.Add(checkPeople);
          //移除listbox1中
          this.listBox2.Items.Remove(checkPeople);
        }
        else
        {
          MessageBox.Show("该人员已经转移过，无法重复转移！");
        }

      }
      else
      {
        MessageBox.Show("未选中销售人员，无法转移到采购部门！");
      }
    }
  }
}