在winForm的程序里，如何在datagrid中插入comobox?

Question

在winForm的程序里，如何在datagrid中插入comobox?

Answer 1

class  DataGridComboBoxColumn: DataGridColumnStyle  
    { 
        private ComboBox myComboBox = new ComboBox (); 
        private DataView ChoiceDataViewSource; 
        private string ChoiceDisplayField; 
        private string ChoiceValueField; 
        private bool isEditing; 
 
        public DataGridComboBoxColumn(DataView ChoiceDataViewSource,string ChoiceDisplayField,string ChoiceValueField) : base()  
        { 
            this.ChoiceDataViewSource =ChoiceDataViewSource; 
            this.ChoiceDisplayField =ChoiceDisplayField; 
            this.ChoiceValueField =ChoiceValueField; 
            myComboBox.DropDownStyle =System.Windows .Forms .ComboBoxStyle .DropDownList  ; 
            myComboBox.Visible = false; 
            myComboBox.DataSource =this.ChoiceDataViewSource; 
            myComboBox.DisplayMember= this.ChoiceDisplayField; 
            myComboBox.ValueMember =this.ChoiceValueField; 
        } 
        protected override void Abort(int rowNum) 
        { 
            isEditing = false; 
            myComboBox.SelectedIndexChanged -=  
                new EventHandler(ComboBoxSelectedIndexChanged ); 
            Invalidate(); 
        } 
 
        protected override bool Commit 
            (CurrencyManager dataSource, int rowNum)  
        { 
            myComboBox.Bounds = Rectangle.Empty; 
          
            myComboBox.SelectedIndexChanged -=  
                new EventHandler(ComboBoxSelectedIndexChanged ); 
 
            if (!isEditing) 
                return true; 
 
            isEditing = false; 
 
            try  
            { 
                System.Object  value = myComboBox.SelectedValue; 
                SetColumnValueAtRow(dataSource, rowNum, value); 
            }  
            catch (Exception)  
            { 
                Abort(rowNum); 
                return false; 
            } 
 
            Invalidate(); 
            return true; 
        } 
 
        protected override void Edit( 
            CurrencyManager source,  
            int rowNum, 
            Rectangle bounds,  
            bool readOnly, 
            string instantText,  
            bool cellIsVisible)  
        { 
            object value =GetColumnValueAtRow(source, rowNum); 
            if (cellIsVisible)  
            { 
                myComboBox.Bounds = new Rectangle 
                    (bounds.X + 2, bounds.Y + 2,  
                    bounds.Width - 4, bounds.Height - 4); 
                int i=    Find (value); 
                if (myComboBox.Items .Count >i)  
                { 
                    myComboBox.SelectedIndex =i; 
                } 
                myComboBox.Visible = true; 
                myComboBox.SelectedIndexChanged +=  
                    new EventHandler(ComboBoxSelectedIndexChanged ); 
            }  
            else  
            { 
                myComboBox.SelectedIndex =this.Find (value); 
                myComboBox.Visible = false; 
            } 
            if (myComboBox.Visible) 
                DataGridTableStyle.DataGrid.Invalidate(bounds); 
        } 
        protected int Find(System.Object value) 
        { 
            int int1; 
            int int2; 
             
            int2=ChoiceDataViewSource.Count ; 
            if (int2<=0) 
            { 
                return -1; 
            } 
            for (int1=0;int1<int2;int1++) 
            { 
                if (ChoiceDataViewSource[int1][this.myComboBox .ValueMember ].ToString ().Trim ()==value.ToString ().Trim ()) 
                { 
                    return int1; 
                } 
            } 
            return -1; 
        } 
 
        protected override Size GetPreferredSize( 
            Graphics g,  
            object value)  
        { 
            return new Size(100, myComboBox.PreferredHeight+ 4); 
        } 
 
        protected override int GetMinimumHeight()  
        { 
            return myComboBox.PreferredHeight + 4; 
        } 
 
        protected override int GetPreferredHeight(Graphics g,  
            object value)  
        { 
            return myComboBox.PreferredHeight + 4; 
        } 
 
        protected override void Paint(Graphics g,  
            Rectangle bounds,  
            CurrencyManager source,  
            int rowNum)  
        { 
            Paint(g, bounds, source, rowNum, false); 
        } 
        protected override void Paint( 
            Graphics g,  
            Rectangle bounds, 
            CurrencyManager source,  
            int rowNum, 
            bool alignToRight)  
        { 
            Paint( 
                g,bounds,  
                source,  
                rowNum,  
                Brushes.Red,  
                Brushes.Blue,  
                alignToRight); 
        } 
        protected override void Paint( 
            Graphics g,  
            Rectangle bounds, 
            CurrencyManager source,  
            int rowNum, 
            Brush backBrush,  
            Brush foreBrush, 
            bool alignToRight)  
        { 
            object value=GetColumnValueAtRow(source, rowNum); 
            int int1=Find (value); 
            string display=""; 
            if (int1>=0) 
            { 
                display=this.ChoiceDataViewSource [int1][this.myComboBox .DisplayMember ].ToString (); 
            } 
            Rectangle rect = bounds; 
            g.FillRectangle(backBrush,rect); 
            rect.Offset(0, 2); 
            rect.Height -= 2; 
            g.DrawString(display,  
                this.DataGridTableStyle.DataGrid.Font,  
                foreBrush, rect); 
        } 
 
        protected override void SetDataGridInColumn(DataGrid value)  
        { 
            base.SetDataGridInColumn(value); 
            if (myComboBox.Parent != null)  
            { 
                myComboBox.Parent.Controls.Remove  
                    (myComboBox); 
            } 
            if (value != null)  
            { 
                value.Controls.Add(myComboBox); 
            } 
        } 
 
        private void ComboBoxSelectedIndexChanged(object sender, EventArgs e)  
        { 
            this.isEditing = true; 
            base.ColumnStartedEditing(myComboBox); 
        } 
    } 
 使用例： 
    表T1（学生档案）    学生ID（主键）  
                                        班级ID_Point 
                                       学生姓名 
    表T2（班级档案)     班级ID（主键） 
                                      班级名称 
    T1.班级ID_Point=T2.班级ID 
    在datagrid显示学生档案时要同时显示班级名称，并可使用下拉列表调整学生所属班级。datagrid的班级ID列可使用DataGridComboBoxColumn列样式。datagrid的DataGridComboBoxColumn(班级ID)列需单独传递班级档案数据源（T2的dataview），显示的字段名称(班级名称)，值字段名称（班级ID)。datagrid生成时先生成各列DataGridColumnStyle（遇到DataGridComboBoxColumn时，load班级档案数据并传参），再生成DataGridTableStyle，将各DataGridColumnStyle加入到DataGridTableStyle，最后将DataGridTableStyle加入到datagrid。

Answer 2

http://blog.csdn.net/zhzuo/archive/2004/05/31/22036.aspx