DATAGRIDVIEW实现双表头及合计栏

经常看到有同好问WINFORM里的DATAGRIDVIEW控件如何能实现双表头及合计栏，想来这是个棘手的问题，首先DATAGRIDVIEW的功能已很强大，重新写个控件费时费力，继承该控件增加一些功能自是首选。但往往做出来效果不大好，表头和合计栏看上去很“假”，不是位置就是外观让人感觉不大对劲。俺琢磨了下，用三个DATAGRIDVIEW“合并”成一个，并实现同步移动，基本可以满足要求，不注意根本看不出是三个拼起来的。

由于俺是业余编程爱好者，水平自是很菜，里面若有BUG，欢迎大家帮俺指正。

代码如下，VS2005编译通过。REBIND方法实现重新绑定、刷新数据的功能。

 

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;

namespace DataGridEx
...{

    public partial class DataGridEx : DataGridView 
    ...{
        private DataGridView FootGrid=null ;
        private DataGridView DoubleGrid = null;
        private bool _footvisible = false;
        private bool _readonly=false ;
        private bool _doublevisible = false;
        private string[] FootText;
        private int[] doubleGridOffset;
        private int initHeight;

        public bool FootVisible
        ...{
            get
            ...{
                return _footvisible;
            }
        }

        public bool DoubleVisible
        ...{
            get
            ...{
                return _doublevisible;
            }
        }

        public bool IsReadOnly
        ...{
            get
            ...{
                return _readonly;
            }
            set
            ...{
                _readonly = value;
                if (_readonly)
                ...{
                    foreach (DataGridViewColumn dv in this.Columns)
                    ...{
                        dv.SortMode = DataGridViewColumnSortMode.NotSortable;
                    }
                }
            }
        }

        public DataGridEx()
        ...{
            InitializeComponent();
        }

        设置DataGrid的列标题显示文字#region 设置DataGrid的列标题显示文字
        /**//// <summary>
        /// 设置DataGrid的列标题显示文字及输出格式。
        /// </summary>
        /// <param name="columnName">要绑定的表字段名</param>
        /// <param name="headText">列标题数组(要和表的列数相等)</param>
        /// <param name="colStyle">列样式(要和表的列数相等)</param>
        /// <param name="colStyle">列宽度(要和表的列数相等)</param>
        public void SetHeadStyle(string[] columnName, string[] headText, string[] colStyle,int[] columnWith)
        ...{
            try
            ...{
                if (columnName.Length == headText.Length && columnName.Length == colStyle.Length)
                ...{
                    DataTable dt = new DataTable();
                    foreach (string col in columnName)
                    ...{
                        dt.Columns.Add(col);
                    }

                    this.DataSource = dt;

                    for (int i = 0; i < headText.Length; i++)
                    ...{
                        if (headText [i]!="")
                        ...{
                            this.Columns[i].HeaderText = headText[i];
                        }

                        if (colStyle[i] != "")
                        ...{
                            this.Columns[i].DefaultCellStyle.Format = colStyle[i];
                        }

                        if (columnWith[i] != 0)
                        ...{
                            this.Columns[i].Width = columnWith[i];
                        }
                    }


                }
                else
                ...{
                    throw new FormatException();
                }
                this.initHeight = this.Height;
            }
            catch (FormatException e)
            ...{
                MessageBox.Show(e.Message+"请重新检查输入数组长度！");
            }
        }

        public void SetHeadStyle(string[] columnName,Type[] colType, string[] headText, string[] colStyle, int[] columnWith)
        ...{
            try
            ...{
                if (columnName.Length == headText.Length && columnName.Length == colStyle.Length)
                ...{
                    DataTable dt = new DataTable();
                    for (int j = 0; j < columnName.Length; j++)
                    ...{
                        dt.Columns.Add(columnName[j], colType[j]);
                    }
                    this.DataSource = dt;

                    for (int i = 0; i < headText.Length; i++)
                    ...{
                        if (headText[i] != "")
                        ...{
                            this.Columns[i].HeaderText = headText[i];
                        }

                        if (colStyle[i] != "")
                        ...{
                            this.Columns[i].DefaultCellStyle.Format = colStyle[i];
                        }

                        if (columnWith[i] != 0)
                        ...{
                            this.Columns[i].Width = columnWith[i];
                        }
                    }


                }
                else
                ...{
                    throw new FormatException();
                }
                this.initHeight = this.Height;
            }
            catch (FormatException e)
            ...{
                MessageBox.Show(e.Message + "请重新检查输入数组长度！");
            }
        }
     #endregion 

        设置合计行#region 设置合计行

        public void SetFoot(string[] columnText)
        ...{
            if (FootGrid == null)
            ...{
                SetFootStyle();
            }
            this.FootText = columnText;
            FootGrid.ColumnCount = this.ColumnCount;
            try
            ...{
                for (int i = 0; i < FootGrid.ColumnCount; i++)
                ...{
                    if (this.Columns[i].Visible)
                    ...{
                        FootGrid.Columns[i].Width = this.Columns[i].Width;
                        FootGrid.Columns[i].SortMode = DataGridViewColumnSortMode.NotSortable;
                        if (columnText[i] != "")
                        ...{
                            FootGrid.Columns[i].HeaderText = this.RowCount == 0 ? (columnText[i] == "S" ? "0" : columnText[i] + "0") :
                             (columnText[i] == "S" ? Convert.ToSingle((this.DataSource as DataTable).Compute("SUM(" + this.Columns[i].Name + ")", "")).ToString(this.Columns[i].DefaultCellStyle.Format) : columnText[i] + this.RowCount);
                        }
                    }
                    else
                    ...{
                        FootGrid.Columns[i].Visible = false;
                    }
                }
            }
            catch (Exception e)
            ...{
                MessageBox.Show(e.Message);
            }
        
        }

        private void SetFootStyle()
        ...{
           
            FootGrid = new DataGridView();
            FootGrid.AllowUserToAddRows = false;
            FootGrid.AllowUserToDeleteRows = false;
            FootGrid.AllowUserToResizeRows = false;
            FootGrid.AllowUserToResizeColumns = false;
            FootGrid.BackgroundColor = this.BackgroundColor;
            FootGrid.BorderStyle = BorderStyle.None ;
            FootGrid.ColumnHeadersBorderStyle = DataGridViewHeaderBorderStyle.Single;
            FootGrid.ColumnHeadersHeightSizeMode = DataGridViewColumnHeadersHeightSizeMode.DisableResizing;
            FootGrid.ColumnHeadersDefaultCellStyle = this.ColumnHeadersDefaultCellStyle;
            FootGrid.GridColor = this.GridColor;
            FootGrid.MultiSelect = false;
            FootGrid.ReadOnly = true;
            FootGrid.RowHeadersVisible = false;
            FootGrid.RowHeadersWidthSizeMode = DataGridViewRowHeadersWidthSizeMode.DisableResizing;
            FootGrid.AllowUserToResizeRows = false;
            FootGrid.ColumnHeadersHeight = this.ColumnHeadersHeight;
            FootGrid.ScrollBars = ScrollBars.Horizontal;
            FootGrid.ShowCellErrors = false;
            FootGrid.ShowEditingIcon = false;
            FootGrid.ShowRowErrors = false;


            int colHeadHeight = (this.Columns.GetColumnsWidth(DataGridViewElementStates.Visible) > this.Width ?
            this.ColumnHeadersHeight * 2 : this.ColumnHeadersHeight);

            this.Height -= colHeadHeight;
            FootGrid.Location = this.Location + new Size(0, this.Height);
            FootGrid.Size = new Size(this.Width, colHeadHeight);
            
            this.Parent.Controls.Add(FootGrid);
            switch (this.Dock)
            ...{
                case DockStyle.Top:
                    FootGrid.BringToFront();
                    FootGrid.Dock = DockStyle.Top;
                    break;
                case DockStyle.None:
                    FootGrid.Dock = DockStyle.None;
                    break;
                default:
                    FootGrid.Dock = DockStyle.Bottom;
                    break;
            }
            this.ScrollBars = ScrollBars.Vertical;
            this._footvisible = true;
            this.FootGrid.Scroll += new ScrollEventHandler(this.FootGrid_Scroll);
            this.ColumnWidthChanged += new DataGridViewColumnEventHandler(this.DataGridEx_ColumnWidthChanged);
            this.DataSourceChanged += new EventHandler(this.DataGridEx_DataSourceChanged);
            this.Scroll -= new ScrollEventHandler(this.DataGridEx_Scroll);
        }
        #endregion

        设置双表头#region 设置双表头

        public void SetDoubleHead(string[] columnText,int[] columnOffset)
        ...{
            if (DoubleGrid == null)
            ...{
                SetDoubleStyle();
            }
            this.doubleGridOffset = columnOffset;
            DoubleGrid.ColumnCount = columnOffset.Length;
            for (int i = 0; i <columnOffset.Length; i++)
            ...{
                if (columnOffset[i] < this.ColumnCount)
                ...{
                    int colwith = 0;
                    for (int j =(i==0?0: columnOffset[i-1] + 1); j <= columnOffset[i]; j++)
                    ...{
                        if (this.Columns[j].Visible)
                        ...{
                            colwith += this.Columns[j].Width;
                        }
                    }
                    DoubleGrid.Columns[i].Width = colwith;
                    DoubleGrid.Columns[i].HeaderText = columnText[i];
                    DoubleGrid.Columns[i].SortMode = DataGridViewColumnSortMode.NotSortable;
                }
            }

        }

        private void SetDoubleStyle()
        ...{
            DoubleGrid = new DataGridView();

            DoubleGrid.AllowUserToAddRows = false;
            DoubleGrid.AllowUserToDeleteRows = false;
            DoubleGrid.AllowUserToResizeRows = false;
            DoubleGrid.AllowUserToResizeColumns = false;
            DoubleGrid.BackgroundColor = this.BackgroundColor;
            DoubleGrid.BorderStyle = BorderStyle.None;
            DoubleGrid.ColumnHeadersBorderStyle = DataGridViewHeaderBorderStyle.Single;
            DoubleGrid.ColumnHeadersHeightSizeMode = DataGridViewColumnHeadersHeightSizeMode.DisableResizing;
            DoubleGrid.ColumnHeadersDefaultCellStyle.BackColor = this.ColumnHeadersDefaultCellStyle.BackColor ;
            DoubleGrid.ColumnHeadersDefaultCellStyle.Font = this.ColumnHeadersDefaultCellStyle.Font;
            DoubleGrid.ColumnHeadersDefaultCellStyle.ForeColor = this.ColumnHeadersDefaultCellStyle.ForeColor;
            DoubleGrid.ColumnHeadersDefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter;
            DoubleGrid.GridColor = this.GridColor;
            DoubleGrid.MultiSelect = false;
            DoubleGrid.ReadOnly = true;
            DoubleGrid.RowHeadersVisible = false;
            DoubleGrid.RowHeadersWidthSizeMode = DataGridViewRowHeadersWidthSizeMode.DisableResizing;
            DoubleGrid.ColumnHeadersHeight = this.ColumnHeadersHeight;
            DoubleGrid.ScrollBars = ScrollBars.Horizontal;
            DoubleGrid.ShowCellErrors = false;
            DoubleGrid.ShowEditingIcon = false;
            DoubleGrid.ShowRowErrors = false;


            DoubleGrid.Location = this.Location;
            this.Height -= this.ColumnHeadersHeight;
            this.Location += new Size(0, this.ColumnHeadersHeight);
            DoubleGrid.Size = new Size(this.Width, this.ColumnHeadersHeight);
            this.ColumnWidthChanged += new DataGridViewColumnEventHandler(this.DataGridEx_ColumnWidthChanged);
            this.Parent.Controls.Add(DoubleGrid);
            switch (this.Dock)
            ...{
                case DockStyle.Bottom:
                    DoubleGrid.BringToFront();
                    DoubleGrid.Dock = DockStyle.Bottom;
                    break;
                case DockStyle.None:
                    DoubleGrid.Dock = DockStyle.None;
                    break;
                default:
                    DoubleGrid.Dock = DockStyle.Top;
                    break;
            }
            this._doublevisible = true;

        }
        #endregion

        public void ReBind()
        ...{
            if (_footvisible)
            ...{
                try
                ...{
                    FootGrid.HorizontalScrollingOffset = 0;

                    decimal[] Compute = new decimal[FootText.Length];
                    for (int j = 0; j < this.ColumnCount; j++)
                    ...{
                        if (FootText[j] != string.Empty)
                        ...{
                            if (FootText[j] == "S")
                            ...{
                                for (int k = 0; k < this.RowCount; k++)
                                ...{
                                    Compute[j] += Convert.ToDecimal(this[j, k].Value == DBNull.Value ? 0 : this[j, k].Value);
                                }
                                FootGrid.Columns[j].HeaderText = Compute[j].ToString(this.Columns[j].DefaultCellStyle.Format);
                            }
                            else
                            ...{
                                FootGrid.Columns[j].HeaderText = FootText[j] + this.RowCount;
                            }
                        }
                    }
                }
                catch (DataException e)
                ...{
                    MessageBox.Show(e.Message + "请重新设置数据格式！");
                }
            }
        }

        private void FootGrid_Scroll(object sender, ScrollEventArgs e)
        ...{
            if (e.ScrollOrientation == ScrollOrientation.HorizontalScroll)
            ...{
                this.DoubleBuffered = true;
                this.HorizontalScrollingOffset = e.NewValue;
                if (DoubleGrid != null)
                ...{
                    DoubleGrid.HorizontalScrollingOffset = e.NewValue;
                }
                this.DoubleBuffered = false;
            }
        }

        private void DataGridEx_Scroll(object sender, ScrollEventArgs e)
        ...{
            if (DoubleGrid != null && FootGrid == null && e.ScrollOrientation == ScrollOrientation.HorizontalScroll)
            ...{
                DoubleGrid.HorizontalScrollingOffset = e.NewValue;
            }
        }

        private void DataGridEx_DataSourceChanged(object sender, EventArgs e)
        ...{
            ReBind();
        }

        private void DataGridEx_ColumnHeaderMouseClick(object sender, DataGridViewCellMouseEventArgs e)
        ...{
            if (_footvisible )
            ...{
                this.HorizontalScrollingOffset = FootGrid.HorizontalScrollingOffset;
            }
        }



        private void DataGridEx_ColumnWidthChanged(object sender, DataGridViewColumnEventArgs e)
        ...{
            if (_footvisible)
            ...{
                this.HorizontalScrollingOffset = FootGrid.HorizontalScrollingOffset;
                int colHeadHeight = (this.Columns.GetColumnsWidth(DataGridViewElementStates.Visible) > this.Width ?
                    FootGrid.ColumnHeadersHeight * 2 : FootGrid.ColumnHeadersHeight);

                this.Height = initHeight - colHeadHeight - (_doublevisible ? FootGrid.ColumnHeadersHeight : 0);
                FootGrid.Location = this.Location + new Size(0, this.Height);
                FootGrid.Size = new Size(this.Width, colHeadHeight);

                int index = e.Column.Index;
                FootGrid.Columns[index].Width = e.Column.Width;
                
            }
            if (_doublevisible)
            ...{
                int offset=0;
                for (int i = 0; i < doubleGridOffset.Length; i++)
                ...{
                    if (e.Column.Index <= doubleGridOffset[i])
                    ...{
                        offset = i;
                        break;
                    }
                }
                DoubleGrid.Columns[offset].Width  = 5;
                for (int j = (offset == 0 ? 1 : doubleGridOffset[offset - 1] + 1); j <= doubleGridOffset[offset]; j++)
                ...{
                    if (this.Columns[j].Visible)
                    ...{
                        DoubleGrid.Columns[offset].Width  += this.Columns[j].Width;
                    }
                 }
                DoubleGrid.Columns[offset].Width -= 5;
                DoubleGrid.HorizontalScrollingOffset = FootGrid.HorizontalScrollingOffset;
            }
        }

        private void DataGridEx_VisibleChanged(object sender, EventArgs e)
        ...{
            if (FootGrid!=null )
            ...{
                FootGrid.Visible =this .Visible;
            }
        }

        private void DataGridEx_CellMouseDown(object sender, DataGridViewCellMouseEventArgs e)
        ...{
            if (e.Button == MouseButtons.Right && e.RowIndex > -1)
            ...{
                this.Rows[e.RowIndex].Selected = true;
            }
        }

        private void DataGridEx_KeyPress(object sender, KeyPressEventArgs e)
        ...{
            if (e.KeyChar==(char)Keys.Space && this.CurrentRow !=null )
            ...{
                this.OnCellDoubleClick(new DataGridViewCellEventArgs(0 , this.CurrentRow.Index));
            }
        }
            

    }


}

 

说明：DATAGRIDVIEW里提供了SCROLL事件，可以做出滚动条同步的效果。另外新增的COLUMNWIDTHCHANGED事件，可以在主表列宽改变时同步改变合计栏、双表头的列宽。