Question

我试图绘制一个对象并移动它，但是它不起作用。我的错误在哪里，我该如何解决？

using System;
using System.Windows.Forms;
using System.Drawing;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        int x = 100, y = 100;
        public Form1()
        {
            InitializeComponent();
        }



        private void Form1_Paint(object sender, PaintEventArgs e)
        {
            e.Graphics.FillRectangle((Brushes.Red), x, y, 20, 20);
        }

        private void Form1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyData == Keys.Right)
            {
                x += 5;
            }

            if (e.KeyData == Keys.Left)
            {
                x -= 5;
            }
            if (e.KeyData == Keys.Up)
            {
                y -= 5;
            }
            if (e.KeyData == Keys.Down)
            {
                y += 5;
            }
        }

        private void moveTimer_Tick(object sender, EventArgs e)
        {
            Invalidate();
        }
    }

Answer 1

您是如此亲密。这是一个快速修复，请寻找一些细微的差异。

using System;
using System.Drawing;
using System.Windows.Forms;


namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        int x = 100, y = 100;

        public Form1()
        {
            InitializeComponent();
        }

        private Rectangle myShape;

        private void Form1_Load(object sender, EventArgs e)
        {
            myShape = new Rectangle(x, y, 20, 20);
        }

        private void Form1_Paint(object sender, PaintEventArgs e)
        {
            e.Graphics.FillRectangle((Brushes.Red), myShape);
        }

        private void Form1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyData == Keys.Right)
            {
                myShape.X += 5;
            }

            if (e.KeyData == Keys.Left)
            {
                myShape.X -= 5;
            }

            if (e.KeyData == Keys.Up)
            {
                myShape.Y -= 5;
            }

            if (e.KeyData == Keys.Down)
            {
                myShape.Y += 5;
            }

            this.Refresh();
        }           
    }
}

如何绘制对象并使用箭头键移动它？

1 个答案: