在DataGridView控件中加入ComboBox下拉列表框的实现

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 ]  =   " 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 " ;
                    }
                }
            }
        }
    }
}