FxGrid出世(附带完整源代码)

 经过6天的连续奋战，FxGrid组件开发完成，今天正式投入使用。这个我把这个Grid作为一个轻量级组件，以弥补开发上的部分需求。

现在介绍一下这个组件的特点：
1、支持界面设计，能够设计出任意复杂的表头；
2、能够设计每个字段的汇总行为，汇总行为包括：None,Sum,Avg,Count；
3、能够设定每个字段的中文显示名称；
4、能够设定每个字段的数据对其方式；
5、能够设定表头的颜色；
6、能够设定每个字段的只读属性；
7、双击单元格，触发双击事件；
8、提供扩展接口，当某行某个单元格被选中时，通过该接口，能够控制该单元格的只读属性(该能够能够满足复杂表格数据的编辑)
9、支持DataTable和DataView数据源

该组件的缺点：
1、不支持鼠标滚轮；
2、是一个.Net组件，只能运行于.Net环境中。

该组件存在的理由：
1、通过表格作为录入界面时，要求表格的表头能够显示更加复杂的内容；
2、作为表格，能够设定是否需要显示合计值；
3、当有需求要求将查询数据和操作数据放在起一处理时(这样做的好处是减少界面数量)，该组件的扩展接口提供了对当前选择单元格的只读属性的控制功能。

总而言之，这个表格没有PowerBuilder的DataWindow那么强大，也没有Crystal Report那么华丽，它只是一个轻量级的Grid(和我自己一样^_^)，对于它的诞生理由，我一直都在思考，我也希望各位能够各抒己见。
（有关Grid的设计，我会继续下去，这个控件太具有挑战性了。但是下面的路该怎么走，我有几点想法：
1、参照MFC中的View概念，去研究
2、.Net下有关控件的构造
以上是技术上的考虑，从需求分析上
3、进一步细化开发中对Grid的需求，这种细化方法和商人细化市场的思想差不多）

以下是这个组件的源代码，用C++.Net编写完成，由于本人对C++.Net的使用时间只有2个多月，代码拙劣的地方还请高手指教。
(Afx是微软的开发团队，Fx是我自己的定义，呵呵！
这个组件不足之处，希望各位不吝赐教。
有关组件设计与系统分析，非常希望能够和更多的朋友交流。联系QQ:64528619)

 设计视图(上传了半天图片，没有成功，只有等改天了)

 

#pragma  once

namespace  FxSystem
... {
    namespace FxForms
    ...{
        using namespace System;
        using namespace FxSystem::FxData;
        using namespace System::Data;
        using namespace System::Windows::Forms;


        public __value enum FxGridColumnAction
        ...{
            None,//什么也不做
            Count,//计算
            Sum,//合计
            Avg//平均值
        };

        public __value enum FxGridColumnStyle
        ...{
            Text,//文本显示样式
            CheckBox//Checkbox显示样式
        };

        //字段标题
    public __gc class FxGridColumn : public Label
    ...{
    private://字段
        String __gc* _name;//字段名称
        FxGridColumnAction __value _action;//字段行为
        HorizontalAlignment __value _align;//数据的对其方式
        FxGridColumnStyle __value _style;//显示样式
        bool _readOnly;//是否只读
       
    public:
        FxGridColumn(void):Label(),
            _action(FxGridColumnAction::None),
            _align(HorizontalAlignment::Left),
            _style(FxGridColumnStyle::Text),
            _readOnly(false)
        ...{
        }
        __property void set_ReadOnly(bool __value value)
        ...{
            this->_readOnly = value;
        }

        __property __value bool get_ReadOnly()
        ...{
            return this->_readOnly;
        }

        __property __value FxGridColumnAction get_Action()
        ...{
            return this->_action;
        }

        __property void set_Action(FxGridColumnAction value)
        ...{
            this->_action = value;
        }

        __property void set_ColName(String __gc* value)
        ...{
            this->_name = value;
        }

        __property String __gc* get_ColName()
        ...{
            return this->_name;
        }
        __property void set_DataAlign(HorizontalAlignment __value value)
        ...{
            this->_align = value;
        }

        __property __value HorizontalAlignment get_DataAlign()
        ...{
            return this->_align;
        }
        __property void set_ContentsStyle(FxGridColumnStyle __value value)
        ...{
            this->_style = value;
        }

        __property __value FxGridColumnStyle get_ContentsStyle()
        ...{
            return this->_style;
        }
    };


    //表格汇总字段列表
    public __gc class FxGridBottomItem :public Label
    ...{
    private:
        FxGridColumnAction __value _action;//处理方式
        String __gc* _name;//字段名称

    public:
        __property void set_Action(FxGridColumnAction __value value)
        ...{
            this->_action = value;
        }
        __property __value FxGridColumnAction get_Action()
        ...{
            return this->_action;
        }
        __property void set_ColumnName(String __gc* value)
        ...{
            this->_name = value;
        }
        __property String __gc* get_ColumnName()
        ...{
            return this->_name;
        }
    };

        //表格
    public __gc class FxGrid : public Panel
    ...{
    public:
        __delegate void CellModifierHandler(DataRow __gc* row, String __gc* colName, DataGridTextBoxColumn __gc* col);//单元格编辑器
    private:
        Panel __gc* _pHead;//表头容器
        Array __gc* _cols;//数据字段表头列表
        DataGridColumnStyle __gc* _colStyles __gc[];//字段列表
        Panel __gc* _pBottom;//表格的底部
        DataGrid __gc* _theGrid;//表格控件
        DataGridTableStyle __gc* _tbStyle;//表格的显示定义
        Panel __gc* _theGridContainer;//Grid的容器
        HScrollBar __gc* _hScroll;//横向滚动条
        VScrollBar __gc* _vScroll;//纵向滚动条
        int _leftMost,_leftStart;//最左边的位置，左边开始滚动的位置
        int _topMost, _topStart;//最顶端的位置，最顶端开始的位置
        FxForms::FxGrid::CellModifierHandler __gc* _cellModifier;//表格编辑函数指针

    public:
        __event void RowDoubleClick(int rowIndex);//单元格的双击时间

    

        FxGrid():Panel(),_theGrid(0),_leftMost(0),_leftStart(0),_cellModifier(0)
        ...{
            //对添加的控件进行过滤
            this->ControlAdded += __gc new System::Windows::Forms::ControlEventHandler(this,ControlEventHandler);
            
        }

        void Init()//初始化
        ...{
            this->AutoScroll = false;
            this->CreateHeader();
            this->CreateTitleList();
            this->CreateGridColumnStyle();
            this->CreateGridBottom();
            this->CreateGrid();
            this->CreateHScroll();
            this->CreateVScroll();
            this->CreateGridContainer();
        }


        __property void set_CellModifier(FxForms::FxGrid::CellModifierHandler __gc* value)
        ...{
            this->_cellModifier = value;
        }
        __property FxForms::FxGrid::CellModifierHandler __gc*  get_CellModifier()
        ...{
            return this->_cellModifier;
        }
        __property void set_DataTable(DataTable __gc* value)
        ...{
            if (this->_theGrid ==0)
                throw __gc new Exception(S"Grid为空");

            this->_tbStyle->MappingName = value->TableName;
            this->_theGrid->DataSource = value;

            //更新表格
            this->UpdateGrid(value->Rows->Count);

            //绑定表格的处理事件
            value->RowChanged += __gc new DataRowChangeEventHandler(this,DataRowChangeHandler);

        }
        __property void set_DataView(DataView __gc* value)
        ...{
            if (this->_theGrid ==0)
                throw __gc new Exception(S"Grid为空");

            this->_tbStyle->MappingName = value->Table->TableName;
            this->_theGrid->DataSource = value;

            //更新表格
            this->UpdateGrid(value->Count);

            //绑定表格的处理事件
            value->Table->RowChanged += __gc new DataRowChangeEventHandler(this,DataRowChangeHandler);
        }

        //返回当前被选中的行
        __property __value int get_CurrentRowIndex()
        ...{
            return this->_theGrid->CurrentRowIndex;
        }
        
        //创建表头
    private:
        void CreateHeader()
        ...{
            this->_pHead = __gc new Panel;
            this->_pHead->BorderStyle = BorderStyle::FixedSingle;
            
            int maxLeft =0,maxTop =0;//最大宽度，最大高度
            
            for (; this->Controls->Count >0; )
            ...{
                if (this->Controls->Item[0]->Left + this->Controls->Item[0]->Width > maxLeft)
                    maxLeft = this->Controls->Item[0]->Left + this->Controls->Item[0]->Width;

                if (this->Controls->Item[0]->Top + this->Controls->Item[0]->Height > maxTop)
                    maxTop = this->Controls->Item[0]->Top + this->Controls->Item[0]->Height;

                this->_pHead->Controls->Add(this->Controls->Item[0]);    
                
            }
            //清空对原有控件的引用
            this->Controls->Clear();
            this->Controls->Add(this->_pHead);

            //计算最大宽度和最大高度
            this->_pHead->Top = 0;
            this->_pHead->Left = 0;
            this->_pHead->Width = maxLeft;
            this->_pHead->Height = maxTop;
        
                        
        }


        //创建数据列表
        void CreateTitleList()
        ...{
            ArrayList __gc* cols = __gc new ArrayList(32);
            for (int i = 0; i<this->_pHead->Controls->Count; i++)
            ...{
                if (this->_pHead->Controls->Item[i]->GetType()->ToString()->CompareTo(S"FxSystem.FxForms.FxGridColumn") == 0)
                    cols->Add(this->_pHead->Controls->Item[i]);
            }

            this->_cols = cols->ToArray(__typeof(FxGridColumn));

            //根据left属性从新排列
            FxGridColumn __gc* buffer;
            FxGridColumn __gc* item;//比较缓存，比较指针

            for (int i = 0; i < this->_cols->Count; i++)
            ...{
                buffer = static_cast<FxGridColumn __gc*>(this->_cols->Item[i]);
                for (int j = i+1;j<this->_cols->Count; j++)
                ...{
                    item = static_cast<FxGridColumn __gc*>(this->_cols->Item[j]);

                    if (buffer ->Left > item->Left)//移动位置
                    ...{
                        this->_cols->Item[i] = this->_cols->Item[j];
                        this->_cols->Item[j] = buffer;
                        buffer = static_cast<FxGridColumn __gc*>(this->_cols->Item[i]);
                    }
                }
            }


        }

        //创建Grid字段定义
        void CreateGridColumnStyle()
        ...{
            
            this->_colStyles = __gc new DataGridColumnStyle __gc* __gc[this->_cols->Count];
            FxGridColumn __gc* item;
            //设置列属性
            for (int i = 0; i< this->_cols->Count; i++)
            ...{
                item  = static_cast<FxGridColumn __gc*>(this->_cols->Item[i]);
                //创建列样式
                if (item->ContentsStyle == FxSystem::FxForms::FxGridColumnStyle::Text)
                ...{
                    DataGridTextBoxColumn __gc* col = __gc new DataGridTextBoxColumn;
                    col->TextBox->DoubleClick += __gc new EventHandler(this,GridDoubleClick);//绑定双击事件
                    col->NullText = S"";
                    
                    this->_colStyles[i] = col;
                    
                }
                else
                    this->_colStyles[i] = __gc new DataGridBoolColumn;
                
                //设置列宽
                this->_colStyles[i]->Width = item->Width;

                //设置对其方式
                this->_colStyles[i]->Alignment = item->DataAlign;

                //设置数据映射名称
                this->_colStyles[i]->MappingName = item->ColName;

                //确定只读方式
                this->_colStyles[i]->ReadOnly = item->ReadOnly;

            }
        }

        //创建表格的底部
        void CreateGridBottom()
        ...{
            this->_pBottom = __gc new Panel;
            FxGridColumn __gc* item;
            FxGridBottomItem __gc* bottomItem;

            for (int i = 0; i < this->_cols->Count; i++)
            ...{
                item = static_cast<FxGridColumn __gc*>(this->_cols->Item[i]);
                bottomItem = __gc new FxGridBottomItem;
                this->_pBottom->Controls->Add(bottomItem);
                bottomItem->Top = 0;
                bottomItem->Left = item->Left;
                bottomItem->Width = item->Width;
                bottomItem->Action = item->Action;
                bottomItem->Height = 20;
                bottomItem->BorderStyle = BorderStyle::FixedSingle;
                bottomItem->ColumnName = item->ColName;
            }
            this->_pBottom->Height = 20;
            this->_pBottom->Width = this->_pHead->Width;

        }

        //创建表格
        void CreateGrid()
        ...{
            this->_theGrid = __gc new DataGrid;
            this->_theGrid->CaptionVisible = false;
            this->_theGrid->BackgroundColor =  System::Drawing::Color::White;
            this->_theGrid->RowHeaderWidth=0;
            this->_theGrid->ColumnHeadersVisible=false;

            this->_tbStyle = __gc new DataGridTableStyle;
            this->_tbStyle->RowHeadersVisible = false;
            this->_tbStyle->RowHeaderWidth = 0;
            this->_tbStyle->PreferredRowHeight = 20;

            //添加列定义
            for (int i = 0; i < this->_colStyles->Count; i++   )
            ...{
                DataGridColumnStyle __gc* item = static_cast<DataGridColumnStyle __gc*>(this->_colStyles->Item[i]);
                this->_tbStyle->GridColumnStyles->Add(item);
            }
            this->_theGrid->TableStyles->Add(this->_tbStyle);

            //添加事件
            this->_theGrid->CurrentCellChanged += __gc new EventHandler(this, CurrentCellChangedHandler);

        }

            //创建横向滚动条
        void CreateHScroll()
        ...{
            this->_hScroll = __gc new HScrollBar;
            this->Controls->Add(this->_hScroll);
            this->_hScroll->Visible = false;
            this->_hScroll->Height = 20;//高度为20
        }

        //创建纵向滚动条
        void CreateVScroll()
        ...{
            this->_vScroll = __gc new VScrollBar;
            this->Controls->Add(this->_vScroll);
            this->_vScroll->Visible = false;
            this->_vScroll->Width = 20;
            this->_vScroll->BringToFront();
        }



        //创建表格容器
        void CreateGridContainer()
        ...{
            this->_theGridContainer = __gc new Panel;
            this->Controls->Add(this->_theGridContainer);
            this->_theGridContainer->Location = System::Drawing::Point(0,0);

            this->_theGridContainer->BorderStyle = BorderStyle::FixedSingle;
            this->_theGridContainer->Width = this->Width - this->_vScroll->Width;
            this->_theGridContainer->Top = this->_pHead->Height;
            this->_theGridContainer->Height = this->Height - this->_pHead->Height - this->_hScroll->Height;
            this->_theGridContainer->Controls->Add(this->_theGrid);
            this->_theGrid->Location = System::Drawing::Point(0,0);
            
            //调整滚动条的位置
            this->_vScroll->Left = this->_theGridContainer->Width;
            this->_vScroll->Top = 0;//this->_theGridContainer->Top;
            this->_vScroll->Height = this->_theGridContainer->Height + this->_pHead->Height;
            this->_vScroll->Visible = true;
            this->_hScroll->Left = 0;
            this->_hScroll->Width = this->_theGridContainer->Width;
            this->_hScroll->Top = this->_theGridContainer->Top + this->_theGridContainer->Height;
            this->_hScroll->Visible=true;

            //调整Grid的位置
            this->_theGrid->Width = this->_pHead->Width + this->_theGrid->RowHeaderWidth + 2;
            this->_theGrid->Width += this->_cols->Count;
            this->_theGrid->Height = this->_theGridContainer->Height - this->_pBottom->Height;

            
            //调整Head的位置，加上RowHeaderWidth
            this->_pHead->Left = this->_theGrid->RowHeaderWidth+2;

            //显示表格的底部
            this->_theGridContainer->Controls->Add(this->_pBottom);
            this->_pBottom->Left = this->_pHead->Left;
            this->_pBottom->Top = this->_theGrid->Height ;

            //横向滚动条的相关设置
            this->_leftStart = this->_pHead->Left;
            this->_leftMost -= (this->_pHead->Width - this->_theGridContainer->Width + this->_pHead->Left);
            this->_hScroll->Maximum = this->_leftStart - this->_leftMost;
            this->_hScroll->SmallChange = 5;
            this->_hScroll->Scroll += __gc new ScrollEventHandler(this,HScrollEvent);

            //纵向滚动条相关设置
            this->_vScroll->Maximum = 0;    
            this->_vScroll->Scroll += __gc new ScrollEventHandler(this,VScrollEvent);
            
           }

        //横向滚动条滚动事件
        void HScrollEvent(
            Object __gc* sender,
            ScrollEventArgs __gc* e
            )...{
                int newleft = 0;//新位置
                newleft = this->_leftStart - e->NewValue;
                if (newleft > this->_leftMost)
                ...{
                    this->_pHead->Left = newleft;
                    this->_pBottom->Left = newleft;
                    this->_theGrid->Left = newleft - this->_theGrid->RowHeaderWidth -2;
                }
                else
                ...{
                    this->_pHead->Left = this->_leftMost;
                    this->_pBottom->Left = this->_leftMost;
                    this->_theGrid->Left = this->_leftMost - this->_theGrid->RowHeaderWidth -2;
                }
            }

            //纵向滚动条滚动事件
        void VScrollEvent(
            Object __gc* sender,
            ScrollEventArgs __gc* e
            )...{
                int newTop = 0;//新位置
                newTop = this->_topStart - e->NewValue;
                if (newTop > this->_topMost)
                ...{
                    this->_theGrid->Top = newTop;
                    this->_pBottom->Top = newTop + this->_theGrid->Height;
                }
                else
                ...{
                    this->_theGrid->Top = this->_topMost;
                    this->_pBottom->Top = this->_topMost + this->_theGrid->Height;
                }
            }

        //更新数据
        void UpdateGrid(int rows/**//*数据数量*/)
        ...{
            //计算数据行的高度
            if (rows < 1)
                return;

            int height = 0;//当前加载数据后的实际高度
            int viewHeight = 0;//表格容器的高度

            height = (rows + 4) * this->_tbStyle->PreferredRowHeight ;//数据的实际高度

            viewHeight = this->_theGridContainer->Height - this->_pBottom->Height;

            if (height > viewHeight)//需要显示滚动条
            ...{
                this->_theGrid->Height = height;
                this->_topStart = 0;
                this->_topMost = viewHeight - height;
                this->_pBottom->Top = height;
                this->_vScroll->Maximum = this->_topStart - this->_topMost + this->_pBottom->Height;
                this->_vScroll->SmallChange = this->_tbStyle->PreferredRowHeight;
            }
            else//不需要显示滚动条
            ...{
                this->_topMost = 0;
                this->_topStart = 0;
                this->_vScroll->Maximum = 0;
                this->_theGrid->Height = this->_theGridContainer->Height - this->_pBottom->Height;
            }

            //重新计算合计
            this->CalSum();
        }

        //Cell的双击处理
        void GridDoubleClick(
            Object* sender,
            EventArgs* e
            )...{
                if (this->_theGrid->CurrentRowIndex >= 0)
                    this->RowDoubleClick(this->_theGrid->CurrentRowIndex + 1);
            }

        
        
        //处理合计
        void CalSum()
        ...{
            if (this->_theGrid->DataSource == 0)
                return;

            if (this->_theGrid->DataSource->GetType()->Equals(__typeof(System::Data::DataTable)))//DataTable
            ...{
                System::Data::DataTable __gc* data = static_cast<System::Data::DataTable __gc*>(this->_theGrid->DataSource);
                FxGridBottomItem __gc* item;

                //计算DataTable的合计
                for (int i =0; i< this->_pBottom->Controls->Count;i++)
                ...{
                    item = static_cast<FxGridBottomItem __gc*>(this->_pBottom->Controls->Item[i]);
                    if (item->Action == FxForms::FxGridColumnAction::Sum)//合计计算
                    ...{
                        item->Text = Convert::ToString(
                            FxSystem::FxData::DataTableCalculator::Sum(data,item->ColumnName)
                            );
                        break;
                    }
                    else if (item->Action == FxForms::FxGridColumnAction::Avg)//平均值计算
                    ...{
                        item->Text = Convert::ToString(
                            FxSystem::FxData::DataTableCalculator::Avg(data,item->ColumnName)
                            );

                    }
                    else if(item->Action == FxForms::FxGridColumnAction::Count)//计算数量
                    ...{
                        item->Text = Convert::ToString(
                            data->Rows->Count
                            );
                    }
                }
            }
            else if (this->_theGrid->DataSource->GetType()->Equals(__typeof(System::Data::DataView)))//DataView
            ...{
                System::Data::DataView __gc* data = static_cast<System::Data::DataView __gc*>(this->_theGrid->DataSource);
                FxGridBottomItem __gc* item;
                //计算DataView的合计
                for (int i =0; i<this->_pBottom->Controls->Count;i++)
                ...{
                    item = static_cast<FxGridBottomItem __gc*>(this->_pBottom->Controls->Item[i]);
                    if (item->Action == FxForms::FxGridColumnAction::Sum)//合计计算
                    ...{
                        item->Text = Convert::ToString(
                            FxData::DataViewCalculator::Sum(data,item->ColumnName)
                            );
                    }
                    else if (item->Action == FxForms::FxGridColumnAction::Avg)//平均值计算
                    ...{
                        item->Text = Convert::ToString(
                            FxData::DataViewCalculator::Avg(data,item->ColumnName)
                            );

                    }
                    else if(item->Action == FxForms::FxGridColumnAction::Count)//计算数量
                    ...{
                        item->Text = Convert::ToString(
                            data->Count
                            );
                    }
                }
            }
            else
            ...{
                throw __gc new Exception(S"无效的数据源");
            }

        }
        //如果添加的控件不是FxGridColumn,DataGrid,Label，那么抛出异常
        void ControlEventHandler(
            Object* sender,
            ControlEventArgs* e)
        ...{
            if (!(e->Control->GetType()->ToString()->CompareTo(S"System.Windows.Forms.Label") == 0 
                || e->Control->GetType()->ToString()->CompareTo(S"FxSystem.FxForms.FxGridColumn") == 0
                || e->Control->GetType()->ToString()->CompareTo(S"System.Windows.Forms.Panel") == 0 
                || e->Control->GetType()->ToString()->CompareTo(S"System.Windows.Forms.HScrollBar") == 0 
                || e->Control->GetType()->ToString()->CompareTo(S"System.Windows.Forms.VScrollBar") == 0 
                || e->Control->GetType()->ToString()->CompareTo(S"FxSystem.FxForms.FxGridBottomItem") == 0 ))
            ...{
                MessageBox::Show(e->Control->GetType()->ToString());
                throw __gc new Exception(S"该控件只能允许使用Lable、FxGridColumn、Panel、FxGridBottomItem");
            }
        }

        //处理当前单元格变化事件
        void CurrentCellChangedHandler(Object __gc* sender, System::EventArgs __gc* args)
        ...{
            if (this->_cellModifier == 0)
                return;

            if (this->_theGrid->DataSource->GetType()->Equals(__typeof(System::Data::DataTable)))
            ...{
                //检查是否有效
                if (this->_theGrid->CurrentRowIndex<0)
                    return;

                int colIndex = this->_theGrid->CurrentCell.ColumnNumber;
                int rowIndex = this->_theGrid->CurrentRowIndex;
                System::Data::DataTable __gc* data= static_cast<System::Data::DataTable __gc*>(this->_theGrid->DataSource);
                DataGridTextBoxColumn __gc* col = static_cast<DataGridTextBoxColumn __gc*>(this->_tbStyle->GridColumnStyles->Item[colIndex]);
                this->_cellModifier->Invoke(data->Rows->Item[rowIndex],col->MappingName, col);

            }
            else if (this->_theGrid->DataSource->GetType()->Equals(__typeof(System::Data::DataView)))
            ...{
                //检查是否有效
                if (this->_theGrid->CurrentRowIndex<0)
                    return;

                int colIndex = this->_theGrid->CurrentCell.ColumnNumber;
                int rowIndex = this->_theGrid->CurrentRowIndex;
                System::Data::DataView __gc* data= static_cast<System::Data::DataView __gc*>(this->_theGrid->DataSource);
                DataGridTextBoxColumn __gc* col = static_cast<DataGridTextBoxColumn __gc*>(this->_tbStyle->GridColumnStyles->Item[colIndex]);
                this->_cellModifier->Invoke(data->Item[rowIndex]->Row,col->MappingName, col);
            }
            else
            ...{
                throw __gc new Exception(S"无效数据源");
            }
        }

        //当数据变化时的处理
        void DataRowChangeHandler(
            Object __gc* sender,
            DataRowChangeEventArgs __gc* e)
        ...{
            //添加行
            if (e->Action == DataRowAction::Add)
            ...{
                this->UpdateGrid(e->Row->Table->Rows->Count);
                return;
            }

            //删除行
            if (e->Action == DataRowAction::Delete)
            ...{
                this->UpdateGrid(e->Row->Table->Rows->Count);
                return;
            }

            //当前行的数据被成功编辑
            if (e->Action == DataRowAction::Change)
            ...{
                this->CalSum();
                return;
            }
        }
    };
    }
}

 

http://blog.youkuaiyun.com/firefox1/archive/2006/12/05/1431416.aspx