在 C# 中单击圆对象时如何移动它
How do you move a circle object when it is clicked on in C#
我正在尝试用 C# 制作跳棋。单击一块时我无法移动它。现在我只想让它移动到任何地方。它正在做的是在它需要移动时创建一个新的 piece 对象实例。任何帮助都会非常感谢。这是代码。
namespace ChineseCheckers
{
public partial class mainForm : Form
{
private Board thisBoard = new Board();
public event PaintEventHandler paint;
public mainForm()
{
InitializeComponent();
}
private void exitToolStripMenuItem_Click(object sender, EventArgs e)
{
Application.Exit();
}
private void mainForm_Paint(object sender, PaintEventArgs e)
{
int width = 15;
int del = 3;
int ystart = 50;
int xstart = ystart+4 * width;
SolidBrush whiteSB = new SolidBrush(Color.White);
for (int i = 0; i < 17; i++)
{
for (int j = 0; j < 17; j++)
{
if (Board.isSpace(i, j))
{
Space sp = thisBoard.getSpace(i, j);
int xPos = getXFromIndex(i, j, width, xstart, ystart);
int yPos = getYFromIndex(i, j, width, xstart, ystart);
pieceObject piece = new pieceObject(e, xPos - del, yPos - del, getColor(sp));
EventHandler myhandler = new EventHandler((a, b)=>myButton_Click(sender, e, piece));
piece.Click += myhandler;
piece.Size = new System.Drawing.Size(20, 20);
piece.Location = new System.Drawing.Point(xPos - del, yPos - del);
piece.BackColor = getColor(sp);
this.Controls.Add(piece);
}
}
}
}
private int getYFromIndex(int i, int j, int width, int xstart, int ystart)
{
return ystart + (2 * i) * width;
}
private int getIFromXY(int x, int y, int width, int xstart, int ystart)
{
return (y - ystart + width) / (2 * width);
}
private int getXFromIndex(int i, int j, int width, int xstart, int ystart)
{
return xstart + (2 * j - i) * width;
}
private int getJFromXY(int x, int y, int width, int xstart, int ystart)
{
int i = getIFromXY(x, y, width, xstart, ystart);
return (((x - xstart+ width/2) / width) + i) / 2;
}
private Color getColor(Space sp)
{
switch (sp)
{
case Space.Player1:
return Color.Orange;
case Space.Player2:
return Color.Yellow;
case Space.Player3:
return Color.Green;
case Space.Player4:
return Color.Blue;
case Space.Player5:
return Color.Purple;
case Space.Player6:
return Color.Red;
}
return Color.Gray;
}
private void newGameToolStripMenuItem_Click(object sender, EventArgs e)
{
Form currentForm = mainForm.ActiveForm;
currentForm.BackgroundImage = null;
currentForm.BackColor = Color.Black;
currentForm.Width = 600;
currentForm.Height = 650;
Button endTurn = new Button();
endTurn.Location = new Point(485, 575);
endTurn.Text = "End Turn";
endTurn.BackColor = Color.Wheat;
endTurn.Click += new EventHandler(endTurnEvent);
this.Controls.Add(endTurn);
}
public void endTurnEvent(object sender, EventArgs e)
{
System.Console.WriteLine("You have ended your turn!");
}
private void mainForm_MouseClick(object sender, MouseEventArgs e)
{
}
void myButton_Click(Object sender, System.EventArgs e, pieceObject piece)
{
System.Console.WriteLine("Position: " + piece.Location + "Color: " + piece.BackColor);
piece.Location = new Point(40, 40);
}
}
}
public class pieceObject : UserControl
{
// Draw the new button.
public pieceObject(PaintEventArgs e, int xPos, int yPos, Color color)
{
int width = 15;
SolidBrush whiteSB = new SolidBrush(color);
SolidBrush newPiece = new SolidBrush(color);
e.Graphics.FillEllipse(newPiece, xPos, yPos, width, width);
newPiece.Dispose();
}
}
没有 a good, minimal, complete code example 就不可能确定最好的建议是什么。但是考虑到你的问题陈述：
What it is doing is creating a new instance of the piece object when it needs to just move
…至少可以确定导致该错误的具体错误并提供一些建议。
您获得 pieceObject class 的新实例的原因是您在每次引发表单的 Paint 事件时创建它们。重要的是要了解 Paint 事件在每次 Windows 决定 window 需要重绘时引发 。这不是一次性的事情。
根据您目前在设计方面的方向，您似乎真的只希望您放入 Paint 事件处理程序中的代码只执行一次。如果是这样，我建议按如下方式更改代码：
首先，修复 pieceObject 以便它根据需要自行绘制：
public class pieceObject : UserControl
{
private readonly Color _color;
public pieceObject(Color color) { _color = color; }
// Draw the new button.
protected override void OnPaint(PaintEventArgs e)
{
int width = 15;
using (SolidBrush newPiece = new SolidBrush(_color))
{
e.Graphics.FillEllipse(newPiece, 3, 3, width, width);
}
}
}
然后，不要在每次引发表单的 Paint 事件时都创建 pieceObject 实例，只需在创建表单时创建一次：
public mainForm()
{
InitializeComponent();
InitializePieceControls();
}
private void InitializePieceControls()
{
int width = 15;
int del = 3;
int ystart = 50;
int xstart = ystart+4 * width;
for (int i = 0; i < 17; i++)
{
for (int j = 0; j < 17; j++)
{
if (Board.isSpace(i, j))
{
Space sp = thisBoard.getSpace(i, j);
int xPos = getXFromIndex(i, j, width, xstart, ystart);
int yPos = getYFromIndex(i, j, width, xstart, ystart);
pieceObject piece = new pieceObject(getColor(sp));
piece.Click += myButton_Click;
piece.Size = new System.Drawing.Size(20, 20);
piece.Location = new System.Drawing.Point(xPos - del, yPos - del);
// It's not clear why you are doing this, as it will just make
// it impossible to see the ellipse that is drawn by the piece
// itself
piece.BackColor = getColor(sp);
this.Controls.Add(piece);
}
}
}
}
void myButton_Click(object sender, EventArgs e)
{
pieceObject piece = (pieceObject)sender;
System.Console.WriteLine("Position: " + piece.Location + "Color: " + piece.BackColor);
piece.Location = new Point(40, 40);
}
备注：
- 在上面我还删除了几个地方你创建了一个白色的画笔，没有使用它，然后没有处理它。
- 您在
pieceObject 上使用 Click 事件在几个方面是错误的：首先，lambda 表达式捕获了 Paint 事件的发送者和事件参数，不是随事件实际发送的 a 和 b；其次，首先不需要将事件处理程序包装在 lambda 中，因为您可以将 Click 事件的实际 sender 转换为实际上的 pieceObject发送事件。
我正在尝试用 C# 制作跳棋。单击一块时我无法移动它。现在我只想让它移动到任何地方。它正在做的是在它需要移动时创建一个新的 piece 对象实例。任何帮助都会非常感谢。这是代码。
namespace ChineseCheckers
{
public partial class mainForm : Form
{
private Board thisBoard = new Board();
public event PaintEventHandler paint;
public mainForm()
{
InitializeComponent();
}
private void exitToolStripMenuItem_Click(object sender, EventArgs e)
{
Application.Exit();
}
private void mainForm_Paint(object sender, PaintEventArgs e)
{
int width = 15;
int del = 3;
int ystart = 50;
int xstart = ystart+4 * width;
SolidBrush whiteSB = new SolidBrush(Color.White);
for (int i = 0; i < 17; i++)
{
for (int j = 0; j < 17; j++)
{
if (Board.isSpace(i, j))
{
Space sp = thisBoard.getSpace(i, j);
int xPos = getXFromIndex(i, j, width, xstart, ystart);
int yPos = getYFromIndex(i, j, width, xstart, ystart);
pieceObject piece = new pieceObject(e, xPos - del, yPos - del, getColor(sp));
EventHandler myhandler = new EventHandler((a, b)=>myButton_Click(sender, e, piece));
piece.Click += myhandler;
piece.Size = new System.Drawing.Size(20, 20);
piece.Location = new System.Drawing.Point(xPos - del, yPos - del);
piece.BackColor = getColor(sp);
this.Controls.Add(piece);
}
}
}
}
private int getYFromIndex(int i, int j, int width, int xstart, int ystart)
{
return ystart + (2 * i) * width;
}
private int getIFromXY(int x, int y, int width, int xstart, int ystart)
{
return (y - ystart + width) / (2 * width);
}
private int getXFromIndex(int i, int j, int width, int xstart, int ystart)
{
return xstart + (2 * j - i) * width;
}
private int getJFromXY(int x, int y, int width, int xstart, int ystart)
{
int i = getIFromXY(x, y, width, xstart, ystart);
return (((x - xstart+ width/2) / width) + i) / 2;
}
private Color getColor(Space sp)
{
switch (sp)
{
case Space.Player1:
return Color.Orange;
case Space.Player2:
return Color.Yellow;
case Space.Player3:
return Color.Green;
case Space.Player4:
return Color.Blue;
case Space.Player5:
return Color.Purple;
case Space.Player6:
return Color.Red;
}
return Color.Gray;
}
private void newGameToolStripMenuItem_Click(object sender, EventArgs e)
{
Form currentForm = mainForm.ActiveForm;
currentForm.BackgroundImage = null;
currentForm.BackColor = Color.Black;
currentForm.Width = 600;
currentForm.Height = 650;
Button endTurn = new Button();
endTurn.Location = new Point(485, 575);
endTurn.Text = "End Turn";
endTurn.BackColor = Color.Wheat;
endTurn.Click += new EventHandler(endTurnEvent);
this.Controls.Add(endTurn);
}
public void endTurnEvent(object sender, EventArgs e)
{
System.Console.WriteLine("You have ended your turn!");
}
private void mainForm_MouseClick(object sender, MouseEventArgs e)
{
}
void myButton_Click(Object sender, System.EventArgs e, pieceObject piece)
{
System.Console.WriteLine("Position: " + piece.Location + "Color: " + piece.BackColor);
piece.Location = new Point(40, 40);
}
}
}
public class pieceObject : UserControl
{
// Draw the new button.
public pieceObject(PaintEventArgs e, int xPos, int yPos, Color color)
{
int width = 15;
SolidBrush whiteSB = new SolidBrush(color);
SolidBrush newPiece = new SolidBrush(color);
e.Graphics.FillEllipse(newPiece, xPos, yPos, width, width);
newPiece.Dispose();
}
}
没有 a good, minimal, complete code example 就不可能确定最好的建议是什么。但是考虑到你的问题陈述：
What it is doing is creating a new instance of the piece object when it needs to just move
…至少可以确定导致该错误的具体错误并提供一些建议。
您获得 pieceObject class 的新实例的原因是您在每次引发表单的 Paint 事件时创建它们。重要的是要了解 Paint 事件在每次 Windows 决定 window 需要重绘时引发 。这不是一次性的事情。
根据您目前在设计方面的方向，您似乎真的只希望您放入 Paint 事件处理程序中的代码只执行一次。如果是这样，我建议按如下方式更改代码：
首先，修复 pieceObject 以便它根据需要自行绘制：
public class pieceObject : UserControl
{
private readonly Color _color;
public pieceObject(Color color) { _color = color; }
// Draw the new button.
protected override void OnPaint(PaintEventArgs e)
{
int width = 15;
using (SolidBrush newPiece = new SolidBrush(_color))
{
e.Graphics.FillEllipse(newPiece, 3, 3, width, width);
}
}
}
然后，不要在每次引发表单的 Paint 事件时都创建 pieceObject 实例，只需在创建表单时创建一次：
public mainForm()
{
InitializeComponent();
InitializePieceControls();
}
private void InitializePieceControls()
{
int width = 15;
int del = 3;
int ystart = 50;
int xstart = ystart+4 * width;
for (int i = 0; i < 17; i++)
{
for (int j = 0; j < 17; j++)
{
if (Board.isSpace(i, j))
{
Space sp = thisBoard.getSpace(i, j);
int xPos = getXFromIndex(i, j, width, xstart, ystart);
int yPos = getYFromIndex(i, j, width, xstart, ystart);
pieceObject piece = new pieceObject(getColor(sp));
piece.Click += myButton_Click;
piece.Size = new System.Drawing.Size(20, 20);
piece.Location = new System.Drawing.Point(xPos - del, yPos - del);
// It's not clear why you are doing this, as it will just make
// it impossible to see the ellipse that is drawn by the piece
// itself
piece.BackColor = getColor(sp);
this.Controls.Add(piece);
}
}
}
}
void myButton_Click(object sender, EventArgs e)
{
pieceObject piece = (pieceObject)sender;
System.Console.WriteLine("Position: " + piece.Location + "Color: " + piece.BackColor);
piece.Location = new Point(40, 40);
}
备注：
- 在上面我还删除了几个地方你创建了一个白色的画笔，没有使用它，然后没有处理它。
- 您在
pieceObject上使用Click事件在几个方面是错误的：首先，lambda 表达式捕获了Paint事件的发送者和事件参数，不是随事件实际发送的a和b；其次，首先不需要将事件处理程序包装在 lambda 中，因为您可以将Click事件的实际sender转换为实际上的pieceObject发送事件。