虽然在Visual Studio中 DataGridView控件的DataGridViewComboBoxColumn可以实现下拉列表框，但这样的列会在整列中都显示下拉列表框，不太 美观，而且还要用代码实现数据绑定。本文介绍一种只在当前编辑单元格中显示下拉列表框的方法，供大家参考。
首先新建一个Windows应用程序，将主窗体重命名为MainForm，在MainForm中加入一个DataGridView控件，命名为dgv_User。如下图所示：
打开窗体代码窗口，在代码窗口中声明一个ComboBox的控件
// 定义下拉列表框
private ComboBox cmb_Temp = new ComboBox();
我们要绑定的下拉列表框的功能是选择性别，添加如下绑定性别下拉列表框的方法
/// <summary>
/// 绑定性别下拉列表框
/// </summary>
private void BindSex()
{
DataTable dtSex = new DataTable();
dtSex.Columns.Add("Value");
dtSex.Columns.Add("Name");
DataRow drSex;
drSex = dtSex.NewRow();
drSex[0] = "1";
drSex[1] = "男";
dtSex.Rows.Add(drSex);
drSex = dtSex.NewRow();
drSex[0] = "0";
drSex[1] = "女";
dtSex.Rows.Add(drSex);
cmb_Temp.ValueMember = "Value";
cmb_Temp.DisplayMember = "Name";
cmb_Temp.DataSource = dtSex;
cmb_Temp.DropDownStyle = ComboBoxStyle.DropDownList;
}
通常情况下我们都是从数据库中获取数据表（或者数据集），然后绑定到DataGridView中的，这里我们为了避免连接数据库，手中构造一个数据库表，代码如下：
private void BindData()
{
DataTable dtData = new DataTable();
dtData.Columns.Add("ID");
dtData.Columns.Add("Name");
dtData.Columns.Add("Sex");
DataRow drData;
drData = dtData.NewRow();
drData[0] = 1;
drData[1] = "张三";
drData[2] = "1";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 2;
drData[1] = "李四";
drData[2] = "1";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 3;
drData[1] = "王五";
drData[2] = "1";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 4;
drData[1] = "小芳";
drData[2] = "0";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 5;
drData[1] = "小娟";
drData[2] = "0";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 6;
drData[1] = "赵六";
drData[2] = "1";
dtData.Rows.Add(drData);
this.dgv_User.DataSource = dtData;
}
为窗体加载事件添加如下方法，其具体功能有详细说明：
private void MainForm_Load(object sender, EventArgs e)
{
// 绑定性别下拉列表框
BindSex();
//绑定数据表
BindData();
// 设置下拉列表框不可见
cmb_Temp.Visible = false;
// 添加下拉列表框事件
cmb_Temp.SelectedIndexChanged += new EventHandler(cmb_Temp_SelectedIndexChanged);
// 将下拉列表框加入到DataGridView控件中
this.dgv_User.Controls.Add(cmb_Temp);
}
当用户选择的单元格移动到性别这一列时，我们要显示下拉列表框，添加如下事件
private void dgv_User_CurrentCellChanged(object sender, EventArgs e)
{
try
{
if (this.dgv_User.CurrentCell.ColumnIndex == 2)
{
Rectangle rect = dgv_User.GetCellDisplayRectangle(dgv_User.CurrentCell.ColumnIndex, dgv_User.CurrentCell.RowIndex, false);
string sexValue = dgv_User.CurrentCell.Value.ToString();
if (sexValue == "1")
{
cmb_Temp.Text = "男";
}
else
{
cmb_Temp.Text = "女";
}
cmb_Temp.Left = rect.Left;
cmb_Temp.Top = rect.Top;
cmb_Temp.Width = rect.Width;
cmb_Temp.Height = rect.Height;
cmb_Temp.Visible = true;
}
else
{
cmb_Temp.Visible = false;
}
}
catch
{
}
}
当用户选择下拉列表框时改变DataGridView单元格的内容
private void cmb_Temp_SelectedIndexChanged(object sender, EventArgs e)
{
if (((ComboBox)sender).Text == "男")
{
dgv_User.CurrentCell.Value = "男";
dgv_User.CurrentCell.Tag = "1";
}
else
{
dgv_User.CurrentCell.Value = "女";
dgv_User.CurrentCell.Tag = "0";
}
}
当滚动DataGridView或者改变DataGridView列宽时将下拉列表框设为不可见
private void dgv_User_Scroll(object sender, ScrollEventArgs e)
{
this.cmb_Temp.Visible = false;
}
private void dgv_User_ColumnWidthChanged(object sender, DataGridViewColumnEventArgs e)
{
this.cmb_Temp.Visible = false;
}
绑定数据表后将性别列中的每一单元格的Value和Tag属性（Tag为值文本，Value为显示文本）
private void dgv_User_DataBindingComplete(object sender, DataGridViewBindingCompleteEventArgs e)
{
for (int i = 0; i < this.dgv_User.Rows.Count; i++)
{
if (dgv_User.Rows[i].Cells[2].Value != null && dgv_User.Rows[i].Cells[2].ColumnIndex == 2)
{
dgv_User.Rows[i].Cells[2].Tag = dgv_User.Rows[i].Cells[2].Value.ToString();
if (dgv_User.Rows[i].Cells[2].Value.ToString() == "1")
{
dgv_User.Rows[i].Cells[2].Value = "男";
}
else if (dgv_User.Rows[i].Cells[2].Value.ToString() == "0")
{
dgv_User.Rows[i].Cells[2].Value = "女";
}
}
}
}
效果如下图所示：
完整的代码如下：
using System;
using System.Data;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace MyNameSpace
{
public partial class MainForm : Form
{
// 定义下拉列表框
private ComboBox cmb_Temp = new ComboBox();
public MainForm()
{
InitializeComponent();
}
/// <summary>
/// 绑定性别下拉列表框
/// </summary>
private void BindSex()
{
DataTable dtSex = new DataTable();
dtSex.Columns.Add("Value");
dtSex.Columns.Add("Name");
DataRow drSex;
drSex = dtSex.NewRow();
drSex[0] = "1";
drSex[1] = "男";
dtSex.Rows.Add(drSex);
drSex = dtSex.NewRow();
drSex[0] = "0";
drSex[1] = "女";
dtSex.Rows.Add(drSex);
cmb_Temp.ValueMember = "Value";
cmb_Temp.DisplayMember = "Name";
cmb_Temp.DataSource = dtSex;
cmb_Temp.DropDownStyle = ComboBoxStyle.DropDownList;
}
/// <summary>
/// 为避免连接数据库，这里手工构造数据表，实际应用中应从数据库中获取
/// </summary>
private void BindData()
{
DataTable dtData = new DataTable();
dtData.Columns.Add("ID");
dtData.Columns.Add("Name");
dtData.Columns.Add("Sex");
DataRow drData;
drData = dtData.NewRow();
drData[0] = 1;
drData[1] = "张三";
drData[2] = "1";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 2;
drData[1] = "李四";
drData[2] = "1";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 3;
drData[1] = "王五";
drData[2] = "1";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 4;
drData[1] = "小芳";
drData[2] = "0";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 5;
drData[1] = "小娟";
drData[2] = "0";
dtData.Rows.Add(drData);
drData = dtData.NewRow();
drData[0] = 6;
drData[1] = "赵六";
drData[2] = "1";
dtData.Rows.Add(drData);
this.dgv_User.DataSource = dtData;
}
private void MainForm_Load(object sender, EventArgs e)
{
// 绑定性别下拉列表框
BindSex();
//绑定数据表
BindData();
// 设置下拉列表框不可见
cmb_Temp.Visible = false;
// 添加下拉列表框事件
cmb_Temp.SelectedIndexChanged += new EventHandler(cmb_Temp_SelectedIndexChanged);
// 将下拉列表框加入到DataGridView控件中
this.dgv_User.Controls.Add(cmb_Temp);
}
// 当用户移动到性别这一列时单元格显示下拉列表框
private void dgv_User_CurrentCellChanged(object sender, EventArgs e)
{
try
{
if (this.dgv_User.CurrentCell.ColumnIndex == 2)
{
Rectangle rect = dgv_User.GetCellDisplayRectangle(dgv_User.CurrentCell.ColumnIndex, dgv_User.CurrentCell.RowIndex, false);
string sexValue = dgv_User.CurrentCell.Value.ToString();
if (sexValue == "1")
{
cmb_Temp.Text = "男";
}
else
{
cmb_Temp.Text = "女";
}
cmb_Temp.Left = rect.Left;
cmb_Temp.Top = rect.Top;
cmb_Temp.Width = rect.Width;
cmb_Temp.Height = rect.Height;
cmb_Temp.Visible = true;
}
else
{
cmb_Temp.Visible = false;
}
}
catch
{
}
}
// 当用户选择下拉列表框时改变DataGridView单元格的内容
private void cmb_Temp_SelectedIndexChanged(object sender, EventArgs e)
{
if (((ComboBox)sender).Text == "男")
{
dgv_User.CurrentCell.Value = "男";
dgv_User.CurrentCell.Tag = "1";
}
else
{
dgv_User.CurrentCell.Value = "女";
dgv_User.CurrentCell.Tag = "0";
}
}
// 滚动DataGridView时将下拉列表框设为不可见
private void dgv_User_Scroll(object sender, ScrollEventArgs e)
{
this.cmb_Temp.Visible = false;
}
// 改变DataGridView列宽时将下拉列表框设为不可见
private void dgv_User_ColumnWidthChanged(object sender, DataGridViewColumnEventArgs e)
{
this.cmb_Temp.Visible = false;
}
// 绑定数据表后将性别列中的每一单元格的Value和Tag属性（Tag为值文本，Value为显示文本）
private void dgv_User_DataBindingComplete(object sender, DataGridViewBindingCompleteEventArgs e)
{
for (int i = 0; i < this.dgv_User.Rows.Count; i++)
{
if (dgv_User.Rows[i].Cells[2].Value != null && dgv_User.Rows[i].Cells[2].ColumnIndex == 2)
{
dgv_User.Rows[i].Cells[2].Tag = dgv_User.Rows[i].Cells[2].Value.ToString();
if (dgv_User.Rows[i].Cells[2].Value.ToString() == "1")
{
dgv_User.Rows[i].Cells[2].Value = "男";
}
else if (dgv_User.Rows[i].Cells[2].Value.ToString() == "0")
{
dgv_User.Rows[i].Cells[2].Value = "女";
}
}
}
}
}
}