关于画画（重绘）的问题
楼主想要通过按钮（只有在点击后才会出现那张图自己画的图）来实现在Form1上画一张图（图的大小大于窗口的大小，所以设置了滚动条），但是在点击以后就在窗口中出现了话的一部分，但是当楼主想拖动滚动条的时候不仅以前未显示的部分没有出现，而且原来的那部分也不见了；
代码如下
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace 重绘1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
this.AutoScroll = true;
this.BackColor = Color.Pink;
this.AutoScrollMinSize = new Size(10000, 10000);
}
private void weizhi(PaintEventArgs e)
{
Point startPoint=new Point (0,0);
Size location = new Size(1000, 1000);
Rectangle rectangle = new Rectangle(startPoint,location);
e.Graphics.Clip = new Region(rectangle );
}
private void button1_Click(object sender, EventArgs e)
{
huahua();
}
private void huahua()
{
Graphics g = CreateGraphics();
Point startPoint = new Point(0, 0);
Point endPoint = new Point(800, 800);
SolidBrush brush = new SolidBrush(Color.Green);
Pen pen = new Pen(brush, 18);
g.TranslateTransform(AutoScrollPosition.X, AutoScrollPosition.Y);
g.FillEllipse(brush, 0, 0, 120, 120);
g.DrawEllipse(pen, 120, 120, 300, 300);
g.DrawLine(pen, startPoint, endPoint);
g.Dispose();
pen.Dispose();this.BackColor = Color.Pink;
brush.Dispose();
}
private void button2_Click(object sender, EventArgs e)
{
Graphics g = CreateGraphics();
g.Clear(Color.White);
g.Dispose();
}
}
}
类 重绘
[解决办法]
要在 paint事件里处理绘制 要不窗体发生重绘你的画面就不见了
[解决办法]
public partial class Form1 : Form
{
bool bPaint = false;
public Form1()
{
InitializeComponent();
this.AutoScroll = true;
this.BackColor = Color.Pink;
this.AutoScrollMinSize = new Size(10000, 10000);
Paint += new PaintEventHandler(Form1_Paint);
}
void Form1_Paint(object sender, PaintEventArgs e)
{
if (bPaint)
{
huahua(e.Graphics);
}
}
private void weizhi(PaintEventArgs e)
{
Point startPoint = new Point(0, 0);
Size location = new Size(1000, 1000);
Rectangle rectangle = new Rectangle(startPoint, location);
e.Graphics.Clip = new Region(rectangle);
}
private void button1_Click(object sender, EventArgs e)
{
bPaint = true;
this.Invalidate();
}
private void huahua(Graphics g)
{
//Graphics g = CreateGraphics();
Point startPoint = new Point(0, 0);
Point endPoint = new Point(800, 800);
SolidBrush brush = new SolidBrush(Color.Green);
Pen pen = new Pen(brush, 18);
g.TranslateTransform(AutoScrollPosition.X, AutoScrollPosition.Y);
g.FillEllipse(brush, 0, 0, 120, 120);
g.DrawEllipse(pen, 120, 120, 300, 300);
g.DrawLine(pen, startPoint, endPoint);
// g.Dispose();
pen.Dispose();
this.BackColor = Color.Pink;
brush.Dispose();
}
private void button2_Click(object sender, EventArgs e)
{
bPaint = false;
// Graphics g = CreateGraphics();
// g.Clear(Color.White);
// g.Dispose();
this.BackColor = Color.White;
}
}
