怎么在DataGridView中实现右键菜单自定义显示及隐藏列功能？针对这个问题，这篇文章详细介绍了相对应的分析和解答，希望可以帮助更多想解决这个问题的小伙伴找到更简单易行的方法。
1、新建一个自定义控件，命名为：PopupMenuControl。
2、在PopupMenuControl.Designet文件中的InitializeComponent()方法下面，注册以下事件：
this.Paint += new System.Windows.Forms.PaintEventHandler(this.PopupMenuControl_Paint); this.MouseDown += new System.Windows.Forms.MouseEventHandler(this.PopupMenuControl_MouseDown); this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.PopupMenuControl_MouseMove);
3、PopupMenuControl的代码：
public partial class PopupMenuControl : UserControl
{ public delegate void CheckedChanged(int hitIndex, bool isChecked); //勾选改变委托
public event CheckedChanged CheckedChangedEvent; //勾选改变事件
PopupMenuHelper popupMenuHelper = null; //菜单帮助类，主要负责菜单绘制。
public PopupMenuControl()
{
InitializeComponent();
}
public void Initialize(DataGridView dgvTarget)
{
//菜单帮助类实例化
popupMenuHelper = new PopupMenuHelper();
//将列标题添加到items
foreach (DataGridViewColumn column in dgvTarget.Columns)
{
popupMenuHelper.AddItem(column.HeaderText, column.Visible);
}
//菜单绘制
popupMenuHelper.Prepare(CreateGraphics());
Width = popupMenuHelper.Width;
Height = popupMenuHelper.Height;
}
///
/// 绘制
///
///
///
private void PopupMenuControl_Paint(object sender, PaintEventArgs e)
{
popupMenuHelper.Draw(e.Graphics);
}
///
/// 鼠标移过
///
///
///
private void PopupMenuControl_MouseMove(object sender, MouseEventArgs e)
{
if (popupMenuHelper.IsMouseMove(e.X, e.Y))
{
popupMenuHelper.Draw(CreateGraphics());
}
}
///
/// 鼠标按下
///
///
///
private void PopupMenuControl_MouseDown(object sender, MouseEventArgs e)
{
if (popupMenuHelper.IsMouseDown(e.X, e.Y))
{
int hitIndex = popupMenuHelper.HitIndex;
if (hitIndex != -1)
{
bool isChecked = popupMenuHelper.IsCheckedChange(hitIndex, CreateGraphics());
OnCheckedChanged(hitIndex, isChecked);
}
}
}
///
/// 勾选改变
///
///
///
public virtual void OnCheckedChanged(int hitIndex, bool isChecked)
{
CheckedChangedEvent?.Invoke(hitIndex, isChecked);
}
} 4、这上面涉及到一个PopupMenuHelper的帮助类，此帮助类主要是为PopupMenuControl控件实现菜单绘制的功能，其代码如下：
class PopupMenuHelper
{
//变量
private PopupMenuItem hotItem = null; //当前Item
private List items = new List(); //Item集合
private Bitmap bitmap; //位图
private Graphics graphics; //图像
private static readonly int BasicConst = 24; //Item：高度、Image宽度
private static readonly int BasicGap = 3; //四周间距
private static readonly int BasicRows = 3; //较大行数
private static readonly int BasicSide = 10; //Item：CheckBox边长(建议用偶数)
private int totality = 1; //分割总数
private int[] eachWidth = null; //各个宽度
//属性
public int Width { get { return bitmap.Width; } } //宽度
public int Height { get { return bitmap.Height; } } //高度
//PopupMenuItem类
private class PopupMenuItem
{
//属性
public string ItemText { get; set; } //Item文本
public bool IsChecked { get; set; } //勾选状态
//构造函数
public PopupMenuItem(string itemText) : this(itemText, false)
{
}
public PopupMenuItem(string itemText, bool isChecked)
{
ItemText = itemText;
IsChecked = isChecked;
}
}
//无参构造函数
public PopupMenuHelper()
{
}
///
/// 被点击Item的Index
///
public int HitIndex
{
get
{
return items.IndexOf(hotItem);
}
}
///
/// 勾选改变状态
///
/// 被点击Item的Index
/// 图像
///
/// 添加Item
///
/// Item文本
/// Item勾选状态
public void AddItem(string itemText, bool isChecked)
{
items.Add(new PopupMenuItem(itemText, isChecked));
}
///
/// 绘制菜单准备
///
/// 图像
public void Prepare(Graphics g)
{
//获取菜单的宽度及高度
totality = (int)Math.Ceiling((double)items.Count / BasicRows);
eachWidth = new int[totality];
int totalWidth = 0, totalHeight = 0;
double maxTextWidth = 0;
if (totality == 1)
{
totalHeight = items.Count * BasicConst + 2 * BasicGap;
foreach (PopupMenuItem item in items)
{
//SizeF：存储有序浮点数对，通常为矩形的宽度和高度。
SizeF sizeF = g.MeasureString(item.ItemText, SystemInformation.MenuFont);
maxTextWidth = Math.Max(maxTextWidth, sizeF.Width);
}
totalWidth = (int)Math.Ceiling((double)maxTextWidth) + BasicConst + 2 * BasicGap;
eachWidth[0] = (int)Math.Ceiling((double)maxTextWidth) + BasicConst;
}
else
{
totalHeight = BasicRows * BasicConst + 2 * BasicGap;
int rows = 0, cols = 1;
foreach (PopupMenuItem item in items)
{
rows++;
//SizeF：存储有序浮点数对，通常为矩形的宽度和高度。
SizeF sizeF = g.MeasureString(item.ItemText, SystemInformation.MenuFont);
maxTextWidth = Math.Max(maxTextWidth, sizeF.Width);
if (cols < totality)
{
//1..[totality-1]列
if (rows == BasicRows)
{
totalWidth += (int)Math.Ceiling((double)maxTextWidth) + BasicConst;
eachWidth[cols - 1] = (int)Math.Ceiling((double)maxTextWidth) + BasicConst;
maxTextWidth = 0;
cols++;
rows = 0;
}
}
else
{
//totality列
if ((cols - 1) * BasicRows + rows == items.Count)
{
totalWidth += (int)Math.Ceiling((double)maxTextWidth) + BasicConst + 2 * BasicGap;
eachWidth[cols - 1] = (int)Math.Ceiling((double)maxTextWidth) + BasicConst;
}
}
}
}
//图像初始化
bitmap = new Bitmap(totalWidth, totalHeight);
graphics = Graphics.FromImage(bitmap);
}
///
/// 绘制菜单
///
///
public void Draw(Graphics g)
{
Rectangle area = new Rectangle(0, 0, bitmap.Width, bitmap.Height);
graphics.Clear(SystemColors.Menu);
DrawBackground(graphics, area);
DrawItems(graphics);
g.DrawImage(bitmap, area, area, GraphicsUnit.Pixel);
}
///
/// 绘制菜单背景
///
///
///
private void DrawBackground(Graphics g, Rectangle area)
{
//描边
using (Pen borderPen = new Pen(Color.FromArgb(112, 112, 112)))
g.DrawRectangle(borderPen, area);
//Image及Text
int left = BasicGap, top = BasicGap;
if (totality == 1)
{
Rectangle imageArea = new Rectangle(left, top, BasicConst, items.Count * BasicConst);
using (Brush backBrush = new SolidBrush(Color.FromArgb(240, 240, 240)))
g.FillRectangle(backBrush, imageArea);
Rectangle textArea = new Rectangle(left + BasicConst, top, eachWidth[0], items.Count * BasicConst);
using (Brush backBrush = new SolidBrush(Color.FromArgb(255, 255, 255)))
g.FillRectangle(backBrush, textArea);
}
else
{
for (int i = 0; i < totality; i++)
{
Rectangle imageArea = new Rectangle(left, top, BasicConst, BasicRows * BasicConst);
using (Brush backBrush = new SolidBrush(Color.FromArgb(240, 240, 240)))
g.FillRectangle(backBrush, imageArea);
Rectangle textArea = new Rectangle(left + BasicConst, top, eachWidth[i], BasicRows * BasicConst);
using (Brush backBrush = new SolidBrush(Color.FromArgb(255, 255, 255)))
g.FillRectangle(backBrush, textArea);
left += eachWidth[i];
}
}
}
///
/// 绘制所有菜单Item
///
/// 图像
private void DrawItems(Graphics g)
{
int left = BasicGap, top = BasicGap;
int rows = 0, cols = 1;
foreach (PopupMenuItem item in items)
{
if (totality == 1)
{
DrawSingleItem(g, left, ref top, eachWidth[0], item, item == hotItem);
}
else
{
rows++;
DrawSingleItem(g, left, ref top, eachWidth[cols - 1], item, item == hotItem);
//1..[totality-1]列
if (rows % BasicRows == 0)
{
left += eachWidth[cols - 1];
top = BasicGap;
cols++;
rows = 0;
}
}
}
}
///
/// 绘制单个菜单Item
///
/// 图像
/// 图像Top
/// 菜单Item
/// 是否为当前菜单Item
private void DrawSingleItem(Graphics g, int left, ref int top,int width, PopupMenuItem item, bool isHotItem)
{
//Item区域
Rectangle drawRect = new Rectangle(left, top, width, BasicConst);
top += BasicConst;
//Text区域
Rectangle itemTextArea = new Rectangle
(
drawRect.Left + BasicConst,
drawRect.Top,
drawRect.Width - BasicConst,
drawRect.Height
);
//背景色及描边色
if (isHotItem)
{
//HotItem
Rectangle hotItemArea = new Rectangle(drawRect.Left, drawRect.Top, drawRect.Width, drawRect.Height);
using (SolidBrush backBrush = new SolidBrush(Color.FromArgb(214, 235, 255)))
g.FillRectangle(backBrush, hotItemArea);
using (Pen borderPen = new Pen(Color.FromArgb(51, 153, 255)))
g.DrawRectangle(borderPen, hotItemArea);
}
//Text处理
StringFormat itemTextFormat = new StringFormat();
//NoClip：允许显示字形符号的伸出部分和延伸到矩形外的未换行文本。
//NoWrap：在矩形内设置格式时，禁用自动换行功能。
itemTextFormat.FormatFlags = StringFormatFlags.NoClip | StringFormatFlags.NoWrap;
//Near：指定文本靠近布局对齐。
itemTextFormat.Alignment = StringAlignment.Near;
//Center：指定文本在布局矩形中居中对齐(呃，感觉不是很垂直居中，偏上了一些)。
itemTextFormat.LineAlignment = StringAlignment.Center;
//Show：显示热键前缀。
itemTextFormat.HotkeyPrefix = HotkeyPrefix.Show;
SolidBrush textBrush = new SolidBrush(SystemColors.MenuText);
g.DrawString(item.ItemText, SystemInformation.MenuFont, textBrush, itemTextArea, itemTextFormat);
//Checkbox处理
if (item.IsChecked)
{
int checkBoxGap = (int)((drawRect.Height - BasicSide) / 2);
int checkBoxLeft = drawRect.Left + checkBoxGap;
int checkBoxTop = drawRect.Top + checkBoxGap;
//将checkBoxArea的Top减1，与文本的对齐效果稍微好一些。
Rectangle checkBoxArea = new Rectangle(checkBoxLeft, checkBoxTop - 1, BasicSide, BasicSide);
using (Brush checkBoxBrush = new SolidBrush(Color.FromArgb(214, 235, 255)))
g.FillRectangle(checkBoxBrush, checkBoxArea);
using (Pen checkBoxPen = new Pen(Color.FromArgb(51, 153, 255)))
g.DrawRectangle(checkBoxPen, checkBoxArea);
using (Pen checkBoxTick = new Pen(Color.FromArgb(51, 153, 255)))
{
g.DrawLine(checkBoxTick, new Point(checkBoxLeft, checkBoxTop - 1 + (int)(BasicSide / 2)), new Point(checkBoxLeft + (int)(BasicSide / 2), checkBoxTop - 1 + BasicSide));
g.DrawLine(checkBoxTick, new Point(checkBoxLeft + (int)(BasicSide / 2), checkBoxTop - 1 + BasicSide), new Point(checkBoxLeft + BasicSide + BasicGap, checkBoxTop - 1 - BasicGap));
}
}
}
///
/// 点击测试
///
/// X坐标
/// Y坐标
///
/// 是否是鼠标移过
///
/// X坐标
/// Y坐标
///
/// 是否是鼠标按下
///
/// X坐标
/// Y坐标
/// 这个类实现了多菜单页面的功能：即如果DataGridView字段非常的多，可通过产生多列菜单来显示，程序是通过BasicRows变量来控制。
5、新建一个DataGridViewColumnSelector类，此类的功能主要是衔接DataGridView与PopupMenuControl，其代码如下：