有没有办法拉绳然后将其删除？
我使用了以下类来撤销/重做矩形，圆形，直线，箭头类型的形状，但是无法想象我如何删除绘制的字符串。
以下是我在形状列表中添加Rectangle的方法：当我从列表中撤消或重做时，这很有效。
的DrawString
Shape shape = new Shape();
shape.shape = ShapesTypes.ShapeTypes.Rectangle;
shape.CopyTuplePoints(points);
shape.X = StartPoint.X;
shape.Y = StartPoint.Y;
shape.Width = EndPoint.X;
shape.Height = EndPoint.Y;
Pen pen = new Pen(new SolidBrush(penColor), 2);
shape.pen = pen;
undoactions.AddShape(shape);
这就是我绘制文字的方式：
var fontFamily = new FontFamily("Calibri");
var font = new Font(fontFamily, 12, FontStyle.Regular, GraphicsUnit.Point);
Size proposedSize = new Size(int.MaxValue, int.MaxValue);
TextFormatFlags flags = TextFormatFlags.WordEllipsis | TextFormatFlags.NoPadding | TextFormatFlags.PreserveGraphicsClipping | TextFormatFlags.WordBreak;
Size size = TextRenderer.MeasureText(e.Graphics, textAreaValue, font, proposedSize, flags);
Shape shape = new Shape();
shape.shape = ShapesTypes.ShapeTypes.Text;
shape.X = ta.Location.X;
shape.Y = ta.Location.Y;
shape.Width = size.Width;
shape.Height = size.Height;
shape.Value = textAreaValue;
Pen pen = new Pen(new SolidBrush(penColor), 2);
shape.pen = pen;
undoactions.AddShape(shape);
但这不适用于undo-redo list。也许问题在于笔和 font-size ，但我无法弄清楚如何使用带有DrawString的笔。
修改 这是我如何绘制油漆事件
protected override void OnPaint(PaintEventArgs e)
{
e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
foreach (var item in undoactions.lstShape)
{
if (item.shape == ShapesTypes.ShapeTypes.Line)
{
e.Graphics.DrawLine(item.pen, item.X, item.Y, item.Width, item.Height);
}
else if (item.shape == ShapesTypes.ShapeTypes.Pen)
{
if (item.Points.Count > 1)
{
e.Graphics.DrawCurve(item.pen, item.Points.ToArray());
}
}
else if (item.shape == ShapesTypes.ShapeTypes.Text)
{
var fontFamily = new FontFamily("Calibri");
var font = new Font(fontFamily, 12, FontStyle.Regular, GraphicsUnit.Point);
e.Graphics.TextRenderingHint = TextRenderingHint.AntiAlias;
e.Graphics.DrawString(item.Value, font, new SolidBrush(item.pen.Color), new PointF(item.X, item.Y));
}
}
}
Shape.cs
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Drawing
{
public class Shape : ICloneable
{
public ShapesTypes.ShapeTypes shape { get; set; }
public List<Point> Points { get; }
public int X { get; set; }
public int Y { get; set; }
public int Width { get; set; }
public int Height { get; set; }
public Pen pen { get; set; }
public String Value { get; set; }
public Shape()
{
Points = new List<Point>();
}
public void CopyPoints(List<Point> points)
{
for (int i = 0; i < points.Count; i++)
{
Point p = new Point();
p.X = points[i].X;
p.Y = points[i].Y;
Points.Add(p);
}
}
public void CopyCopyPoints(List<List<Point>> points)
{
for (int j = 0; j < points.Count; j++)
{
List<Point> current = points[j];
for (int i = 0; i < current.Count; i++)
{
Point p = new Point();
p.X = current[i].X;
p.Y = current[i].Y;
Points.Add(p);
}
}
}
public void CopyTuplePoints(List<Tuple<Point, Point>> points)
{
foreach (var line in points)
{
Point p = new Point();
p.X = line.Item1.X;
p.Y = line.Item1.Y;
Points.Add(p);
p.X = line.Item2.X;
p.Y = line.Item2.Y;
Points.Add(p);
}
}
public object Clone()
{
Shape shp = new Shape();
shp.X = X;
shp.Y = Y;
shp.Width = Width;
shp.Height = Height;
shp.pen = pen;
shp.shape = shape;
shp.Value = Value;
for (int i = 0; i < Points.Count; i++)
{
shp.Points.Add(new Point(Points[i].X, Points[i].Y));
}
return shp;
}
}
}
画圆
if (currentshape == ShapesTypes.ShapeTypes.Circle)
{
Shape shape = new Shape();
shape.shape = ShapesTypes.ShapeTypes.Circle;
shape.CopyTuplePoints(cLines);
shape.X = StartPoint.X;
shape.Y = StartPoint.Y;
shape.Width = EndPoint.X;
shape.Height = EndPoint.Y;
Pen pen = new Pen(new SolidBrush(penColor), 2);
shape.pen = pen;
undoactions.AddShape(shape);
}
撤消
if (currentshape != ShapesTypes.ShapeTypes.Undo)
{
oldshape = currentshape;
currentshape = ShapesTypes.ShapeTypes.Undo;
}
if (undoactions.lstShape.Count > 0)
{
undoactions.Undo();
this.Invalidate();
}
if (undoactions.redoShape.Count > 0)
{
btnRedo.Enabled = true;
}
UndoRedo
public class UndoRedo
{
public List<Shape> lstShape = new List<Shape>();
public List<Shape> redoShape = new List<Shape>();
public void AddShape(Shape shape)
{
lstShape.Add(shape);
}
public void Undo()
{
redoShape.Add((Shape)lstShape[lstShape.Count - 1].Clone());
lstShape.RemoveAt(lstShape.Count - 1);
}
public void Redo()
{
lstShape.Add((Shape)redoShape[redoShape.Count - 1].Clone());
redoShape.RemoveAt(redoShape.Count - 1);
}
}
答案 0 :(得分：2)
将来，请遵循Minimal, Complete, and Verifiable example的指导原则。这将有助于我们为您提供帮助。例如，您可以排除与克隆相关的所有代码，因为它与您的问题无关。
我稍微重构了你的代码并创建了一个小的，可重现的例子。此示例适用于您概述的一般方法，因此我无法告诉您为什么您的代码无法正常工作，除非您还可以发布一个类似的示例，我可以将其复制/粘贴到我的环境中。请不要链接到外部代码 - 它必须在此处托管。
我重构了它以突出一些语言功能，这些功能可以帮助您的代码更易于维护。如果您对我放在这里的内容有任何疑问，请与我们联系。请让我知道这可不可以帮你。如果没有，请将其用作模板并用您的代码替换我的代码，以便我为您提供帮助。
public partial class Form1 : Form
{
private EntityBuffer _buffer = new EntityBuffer();
private System.Windows.Forms.Button btnUndo;
private System.Windows.Forms.Button btnRedo;
public Form1()
{
this.btnUndo = new System.Windows.Forms.Button();
this.btnRedo = new System.Windows.Forms.Button();
this.SuspendLayout();
this.btnUndo.Location = new System.Drawing.Point(563, 44);
this.btnUndo.Name = "btnUndo";
this.btnUndo.Size = new System.Drawing.Size(116, 29);
this.btnUndo.TabIndex = 0;
this.btnUndo.Text = "Undo";
this.btnUndo.UseVisualStyleBackColor = true;
this.btnUndo.Click += new System.EventHandler(this.btnUndo_Click);
this.btnRedo.Location = new System.Drawing.Point(563, 79);
this.btnRedo.Name = "btnRedo";
this.btnRedo.Size = new System.Drawing.Size(116, 29);
this.btnRedo.TabIndex = 0;
this.btnRedo.Text = "Redo";
this.btnRedo.UseVisualStyleBackColor = true;
this.btnRedo.Click += new System.EventHandler(this.btnRedo_Click);
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(800, 450);
this.Controls.Add(this.btnRedo);
this.Controls.Add(this.btnUndo);
this.Name = "Form1";
this.Text = "Form1";
this.ResumeLayout(false);
}
protected override void OnLoad(EventArgs e)
{
_buffer.Add(new Rectangle(10, 10, 10, 10, Color.Red));
_buffer.Add(new Rectangle(20, 20, 10, 10, Color.Red));
_buffer.Add(new Rectangle(30, 30, 10, 10, Color.Red));
_buffer.Add(new Text(40, 40, "Test", Color.Black));
_buffer.Add(new Rectangle(50, 50, 10, 10, Color.Red));
_buffer.Add(new Text(60, 60, "Test", Color.Black));
base.OnLoad(e);
}
protected override void OnPaint(PaintEventArgs e)
{
foreach (var entity in _buffer.Entities)
entity.Draw(e.Graphics);
base.OnPaint(e);
}
private void btnUndo_Click(object sender, EventArgs e)
{
if (!_buffer.CanUndo)
return;
_buffer.Undo();
Invalidate();
}
private void btnRedo_Click(object sender, EventArgs e)
{
if (!_buffer.CanRedo)
return;
_buffer.Redo();
Invalidate();
}
}
public abstract class Entity
{
public int X { get; set; }
public int Y { get; set; }
public Color Color { get; set; }
public abstract void Draw(Graphics g);
public Entity(int x, int y, Color color)
{
X = x;
Y = y;
Color = color;
}
}
public class Text : Entity
{
private static Font _font = new Font(new FontFamily("Calibri"), 12, FontStyle.Regular, GraphicsUnit.Point);
public string Value { get; set; }
public Text(int x, int y, string value, Color color) : base(x,y,color) => Value = value;
public override void Draw(Graphics g) => g.DrawString(Value, _font, new SolidBrush(Color), new PointF(X, Y));
}
public abstract class Shape : Entity
{
public int Width { get; set; }
public int Height { get; set; }
public Pen Pen { get; set; }
public Shape(int x, int y, int width, int height, Color color) : base(x, y, color)
{
Width = width;
Height = height;
}
}
public class Rectangle : Shape
{
public Rectangle(Point start, Point end, Color color) : this(start.X, start.Y, end.X, end.Y, color) { }
public Rectangle(int x, int y, int width, int height, Color color) : base(x, y, width, height, color) { }
public override void Draw(Graphics g) => g.DrawRectangle(new Pen(new SolidBrush(Color)), X, Y, Width, Height);
}
public class EntityBuffer
{
public Stack<Entity> Entities { get; set; } = new Stack<Entity>();
public Stack<Entity> RedoBuffer { get; set; } = new Stack<Entity>();
public bool CanRedo => RedoBuffer.Count > 0;
public bool CanUndo => Entities.Count > 0;
public void Add(Entity entity)
{
Entities.Push(entity);
RedoBuffer.Clear();
}
public void Undo() => RedoBuffer.Push(Entities.Pop());
public void Redo() => Entities.Push(RedoBuffer.Pop());
}
答案 1 :(得分：1)
您可以创建TextShape衍生自Shape的{{1}}，具有Text，Font，Location和Color属性并像其他一样对待形状，所以重做和撤消不会有问题。
以下提示可帮助您解决问题：
Shape类或界面，其中包含Draw，Clone，HitTest等基本方法。TextShape在内的所有形状都应来自Shape。 TextShape也是一种形状，具有Text，Font，Location和Color属性。Shape的每个实现都有基本方法的实现。INotifyPropertyChanged，然后您可以听取属性的更改，例如，在更改颜色，边框宽度等后添加一些内容到撤消缓冲区。IClonable或基类Clone方法。添加到撤消缓冲区时，所有形状都应该是可克隆的。Pen和Brush等GDI对象。这不是可选的。INotifyPropertyChanged中，然后通过形状或此类属性中的每个更改，您可以将此类的克隆添加到撤消缓冲区。<强>形状
以下是Shape类的示例：
public abstract class Shape : INotifyPropertyChanged {
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string name = "") {
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}
public abstract void Draw(Graphics g);
public abstract Shape Clone();
}
<强> TextShape
注意实现提升PropertyChanged事件的属性以及用于克隆撤消缓冲区对象的Clone方法，以及Draw中使用GDI对象的方式：
public class TextShape : Shape {
private string text;
public string Text {
get { return text; }
set {
if (text != value) {
text = value;
OnPropertyChanged();
}
}
}
private Point location;
public Point Location {
get { return location; }
set {
if (!location.Equals(value)) {
location = value;
OnPropertyChanged();
}
}
}
private Font font;
public Font Font {
get { return font; }
set {
if (font!=value) {
font = value;
OnPropertyChanged();
}
}
}
private Color color;
public Color Color {
get { return color; }
set {
if (color!=value) {
color = value;
OnPropertyChanged();
}
}
}
public override void Draw(Graphics g) {
using (var brush = new SolidBrush(Color))
g.DrawString(Text, Font, brush, Location);
}
public override Shape Clone() {
return new TextShape() {
Text = Text,
Location = Location,
Font = (Font)Font.Clone(),
Color = Color
};
}
}
<强>的DrawingContext
该类实际上包含所有形状和一些其他属性，如绘图表面的背面颜色。这是您需要将其克隆添加到撤消缓冲区的类：
public class DrawingContext : INotifyPropertyChanged {
public DrawingContext() {
BackColor = Color.White;
Shapes = new BindingList<Shape>();
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string name = "") {
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}
private Color backColor;
public Color BackColor {
get { return backColor; }
set {
if (!backColor.Equals(value)) {
backColor = value;
OnPropertyChanged();
}
}
}
private BindingList<Shape> shapes;
public BindingList<Shape> Shapes {
get { return shapes; }
set {
if (shapes != null)
shapes.ListChanged -= Shapes_ListChanged;
shapes = value;
OnPropertyChanged();
shapes.ListChanged += Shapes_ListChanged;
}
}
private void Shapes_ListChanged(object sender, ListChangedEventArgs e) {
OnPropertyChanged("Shapes");
}
public DrawingContext Clone() {
return new DrawingContext() {
BackColor = this.BackColor,
Shapes = new BindingList<Shape>(this.Shapes.Select(x => x.Clone()).ToList())
};
}
}
<强> DrawingSurface
这个类实际上是具有撤消和重做功能的控件，并且还在其表面上绘制当前的绘图上下文：
public class DrawingSurface : Control {
private Stack<DrawingContext> UndoBuffer = new Stack<DrawingContext>();
private Stack<DrawingContext> RedoBuffer = new Stack<DrawingContext>();
public DrawingSurface() {
DoubleBuffered = true;
CurrentDrawingContext = new DrawingContext();
UndoBuffer.Push(currentDrawingContext.Clone());
}
DrawingContext currentDrawingContext;
[DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
[Browsable(false)]
public DrawingContext CurrentDrawingContext {
get {
return currentDrawingContext;
}
set {
if (currentDrawingContext != null)
currentDrawingContext.PropertyChanged -= CurrentDrawingContext_PropertyChanged;
currentDrawingContext = value;
Invalidate();
currentDrawingContext.PropertyChanged += CurrentDrawingContext_PropertyChanged;
}
}
private void CurrentDrawingContext_PropertyChanged(object sender, PropertyChangedEventArgs e) {
UndoBuffer.Push(CurrentDrawingContext.Clone());
RedoBuffer.Clear();
Invalidate();
}
public void Undo() {
if (CanUndo) {
RedoBuffer.Push(UndoBuffer.Pop());
CurrentDrawingContext = UndoBuffer.Peek().Clone();
}
}
public void Redo() {
if (CanRedo) {
CurrentDrawingContext = RedoBuffer.Pop();
UndoBuffer.Push(CurrentDrawingContext.Clone());
}
}
public bool CanUndo {
get { return UndoBuffer.Count > 1; }
}
public bool CanRedo {
get { return RedoBuffer.Count > 0; }
}
protected override void OnPaint(PaintEventArgs e) {
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
using (var brush = new SolidBrush(CurrentDrawingContext.BackColor))
e.Graphics.FillRectangle(brush, ClientRectangle);
foreach (var shape in CurrentDrawingContext.Shapes)
shape.Draw(e.Graphics);
}
}
答案 2 :(得分：0)
在绘制形状并将其尺寸标记为图像上的字符串之后，我做了类似的项目;按 Ctrl-Z / Ctrl-Y 后，它会执行撤消/重做对图像执行的操作。
Here是我的Github项目的链接，一个C＃win-form soln。运行soln后，工具使用说明将出现在工具本身上。
希望这可以帮助你...