• 在DataGridView控件中加入ComboBox下拉列表框的实现


      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= "";
        dtSex.Rows.Add(drSex);
        drSex 
    = dtSex.NewRow();
        drSex[
    0= "0";
        drSex[
    1= "";
        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 
    = "";
                }
                
    else
                {
                    cmb_Temp.Text 
    = "";
                }
                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 == "")
        {
            dgv_User.CurrentCell.Value 
    = "";
            dgv_User.CurrentCell.Tag 
    = "1";
        }
        
    else
        {
            dgv_User.CurrentCell.Value 
    = "";
            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 = "";
                }
                
    else if (dgv_User.Rows[i].Cells[2].Value.ToString() == "0")
                {
                    dgv_User.Rows[i].Cells[
    2].Value = "";
                }
            }
        }
    }

      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= "";
                dtSex.Rows.Add(drSex);
                drSex 
    = dtSex.NewRow();
                drSex[
    0= "0";
                drSex[
    1= "";
                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 
    = "";
                        }
                        
    else
                        {
                            cmb_Temp.Text 
    = "";
                        }
                        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 == "")
                {
                    dgv_User.CurrentCell.Value 
    = "";
                    dgv_User.CurrentCell.Tag 
    = "1";
                }
                
    else
                {
                    dgv_User.CurrentCell.Value 
    = "";
                    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 = "";
                        }
                        
    else if (dgv_User.Rows[i].Cells[2].Value.ToString() == "0")
                        {
                            dgv_User.Rows[i].Cells[
    2].Value = "";
                        }
                    }
                }
            }
        }
    }

     

      文章很长,希望能给您带来帮助。

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  • 原文地址:https://www.cnblogs.com/luqingfei/p/691372.html
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