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如何重新绘制/更新表单的特定部分

Danial Ahmed · 技术社区 · 7 年前

private float[] values;
private int m=0;
public Form1()
{
    InitializeComponent();
    values =new float[Width];
}

private void Form1_Load(object sender, EventArgs e)
{
    Random rnd = new Random();
    for (int i = 0; i < values.Length; i++)
    {
        values[i] = rnd.Next(Height);
    }
}
void bubbleSort()
{
    Task.Run(async () =>
    {
        for (m = 0; m < values.Length; m++)
        {
            for (int j = 0; j < values.Length - m - 1; j++)
            {
                if (values[j] > values[j + 1])
                {
                    float temp = values[j];
                    values[j] = values[j + 1];
                    values[j + 1] = temp;
                    Invalidate();
                }
            }
            await Task.Delay(1000);
        }
    });
    //Update();
}
private void Form1_Paint(object sender, PaintEventArgs e)
{
    //var graphicsObj = this.CreateGraphics();

    Pen blackPen = new Pen(Color.Black, (float)0.5);

    for (int i = 0; i < values.Length; i++)
    {
            e.Graphics.DrawLine(blackPen, i, 0, i, values[i]);
    }
    if (m<values.Length)
    {
        bubbleSort();
    }
}

编辑:增加了延迟气泡排序现在我可以看到它重画和排序,但问题是,它再次重画所有的点。

1 回复 | 直到 7 年前

TaW 7 年前

float[] values =new float[555];
int m=0;

private void startButton_Click(object sender, EventArgs e)
{
    Random rnd = new Random();
    for (int i = 0; i < values.Length; i++)
    {
        values[i] = rnd.Next(Height);
    }
    m=0;
    bubbleSort();
}

排序本身是不变的(从原来的帖子开始!),仅移动更新触发器:

void bubbleSort()
{
    for (m = 0; m < values.Length; m++)
    {
        for (int j = 0; j < values.Length - m - 1; j++)
        {
            if (values[j] > values[j + 1])
            {
                float temp = values[j];
                values[j] = values[j + 1];
                values[j + 1] = temp;
            }
        }
        Refresh();   // Invalidate would be optimized away
    }
}

这个 Paint

private void Form1_Paint(object sender, PaintEventArgs e)
{
    for (int i = 0; i < values.Length; i++)
    {
        e.Graphics.DrawLine(Pens.Black, i, 0, i, values[i]);
        e.Graphics.DrawLine(Pens.White, i,  values[i], i, ClientSize.Height);
    }
}

笔记: