C# DataGridView添加右键菜单等技巧

1).右键点击行时选中行，并弹出操作菜单

1). 添加一个快捷菜单contextMenuStrip1；
2). 给dataGridView1的CellMouseDown事件添加处理程序：

private void DataGridView1_CellMouseDown(object sender, DataGridViewCellMouseEventArgs e){    if (e.Button == MouseButtons.Right)    {        if (e.RowIndex >= 0)        {            //若行已是选中状态就不再进行设置            if (dataGridView1.Rows[e.RowIndex].Selected == false)            {                dataGridView1.ClearSelection();                dataGridView1.Rows[e.RowIndex].Selected = true;            }            //只选中一行时设置活动单元格            if (dataGridView1.SelectedRows.Count == 1)            {                dataGridView1.CurrentCell = dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex];            }            //弹出操作菜单            contextMenuStrip1.Show(MousePosition.X, MousePosition.Y);        }    }}

效果图：



2).复制选中单元格的内容到剪贴板

Clipboard.SetDataObject(dataGridView1.GetClipboardContent());

3).只显示自定义列

dataGridView1.AutoGenerateColumns = false;//必须在代码中设置

4).显示图片

通常，我们将图片路径保存在数据库中，但在dataGridView1中要显示图片，可以进行如下操作：

①.添加一个DataGridViewTextBoxColumn类型的列，Name=Path,DataPropertyName=Pic,Visible=False；
②.添加一个DataGridViewImageColumn类型的列，Name=Pic；
③.dataGridView1控件DataBindingComplete事件处理程序如下：

private void DataGridView1_DataBindingComplete(object sender, DataGridViewBindingCompleteEventArgs e){    Image image1 = null;    Image image2 = null;    string path = string.Empty;    for (int i = 0; i < dataGridView1.Rows.Count; i++)    {        path = @"F:\" + dataGridView1.Rows[i].Cells["Path"].Value;        if (File.Exists(path))        {            image1 = Image.FromFile(path);            image2 = new Bitmap(image1, 120, 120);//重设大小            dataGridView1.Rows[i].Cells["Pic"].Value = image2;            //((DataGridViewImageCell)dataGridView1.Rows[i].Cells["Pic"]).Value = image2;        }    }}

5).当网格未填充满控件时，画线来填充空白区域

/// <summary>/// 绘制网格填充空白区域/// </summary>/// <param name="sender"></param>/// <param name="e"></param>public void CellPainting(object sender, DataGridViewCellPaintingEventArgs e){    DataGridView myDataGridView = (DataGridView)sender;    if (myDataGridView.Rows.Count > 0)    {        int i = myDataGridView.ColumnHeadersHeight;//标题行高        int j = myDataGridView.Rows.GetRowsHeight(DataGridViewElementStates.Visible); //所有可见行总高        int k = myDataGridView.Height; //控件高度        int l = myDataGridView.Rows.GetLastRow(DataGridViewElementStates.Visible);//最后一行索引        int count = myDataGridView.Columns.Count;//列总数        int width = 0;        //当网格未充满控件时才画线        if (i + j < k)        {            using (Brush gridBrush = new SolidBrush(myDataGridView.GridColor))            {                using (Pen gridLinePen = new Pen(gridBrush))                {                    //处理标题列                    if (myDataGridView.RowHeadersVisible)                    {                        width = myDataGridView.RowHeadersWidth;                        e.Graphics.DrawLine(gridLinePen, width, i + j, width, k);                    }                    else                    {                        width = 1;                    }                    //处理正常列                    for (int index = 0; index < count; index++)                    {                        if (myDataGridView.Columns[index].Visible)                        {                            width += myDataGridView.Columns[index].Width;                            e.Graphics.DrawLine(gridLinePen, width, i + j, width, k);                        }                    }                }            }        }    }}

6).自定义列宽

手动添加列，再在编辑列界面中逐个设置宽度。注意AutoSizeColumnsMode的值必须为DataGridViewAutoSizeColumnsMode.None，否则自定义宽度不能生效！

7).单元格内容格式化

private void dataGridView1_CellFormatting(object sender, DataGridViewCellFormattingEventArgs e){    DataGridView myDataGridView = (DataGridView)sender;    if (myDataGridView.Columns["ID"].Index == e.ColumnIndex)    {        if(e.Value != null && !string.IsNullOrEmpty(e.Value.ToString()))            e.Value = "BH" + string.Format("{0:D8}", int.Parse(e.Value.ToString()));    }}

8).打造一个漂亮的DataGridView

//样式dataGridView1.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.None;//列宽不自动调整,手工添加列dataGridView1.RowHeadersWidth = 12;//行标题宽度固定12dataGridView1.RowHeadersWidthSizeMode = DataGridViewRowHeadersWidthSizeMode.DisableResizing;//不能用鼠标调整列标头宽度dataGridView1.AlternatingRowsDefaultCellStyle.BackColor = Color.LemonChiffon;//奇数行背景色dataGridView1.BackgroundColor = Color.White;//控件背景色dataGridView1.ColumnHeadersDefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter;//列标题居中显示dataGridView1.DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter;//单元格内容居中显示//行为dataGridView1.AutoGenerateColumns = false;//不自动创建列dataGridView1.AllowUserToAddRows = false;//不启用添加dataGridView1.ReadOnly = true;//不启用编辑dataGridView1.AllowUserToDeleteRows = false;//不启用删除dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;//单击单元格选中整行dataGridView1.MultiSelect = false;//不能多选

9).判断有无滚动条

//垂直滚动条if (dataGridView1.Rows.GetRowsHeight(DataGridViewElementStates.None) > dataGridView1.Height)    MessageBox.Show("有");else    MessageBox.Show("无");//水平滚动条if(dataGridView1.Columns.GetColumnsWidth(DataGridViewElementStates.None) > dataGridView1.Width)    MessageBox.Show("有");else    MessageBox.Show("无");

10).为什么列标题总不居中？

已经将列标题默认对齐方式设置为居中：

dataGridView1.ColumnHeadersDefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter;//列标题居中显示

但实际的效果总是偏左了一点，原因是列可以进行排序，排序标志符号在列标题上占了空间。逐列按下边设置可去掉：

dataGridView1.Columns[i].SortMode = DataGridViewColumnSortMode.NotSortable;