Question

我想延迟循环，以使其显示我放入的背景色。现在，它只是速度很快。目的是让颜色像迪斯科一样闪烁。我使用了Thread.sleep，但是那是行不通的。

private void Disco(object sender, RoutedEventArgs e)
    {
           for (int n =0; n<=10;n++)
           {
               Background = Brushes.Coral;
               Background = Brushes.AliceBlue;
               Background = Brushes.DarkRed;
               Background = Brushes.Red;
               Background = Brushes.Blue;
               Background = Brushes.Aquamarine;
           }
       }

Answer 1

您可以使用{Jeren van Langen在评论中建议的async方法。

在await Task.Delay(time)次更改之间使用Background将延迟给定time的更改。

private async void Disco(object sender, RoutedEventArgs e)
{
    Background = Brushes.Coral;
    await Task.Delay(500); // 500 is just an example. You can use any number in milliseconds.
    Background = Brushes.AliceBlue;
    await Task.Delay(500);
    Background = Brushes.DarkRed;
    await Task.Delay(500);
    Background = Brushes.Red;
    await Task.Delay(500);
    Background = Brushes.Blue;
    await Task.Delay(500);
    Background = Brushes.Aquamarine;
    await Task.Delay(500);
    //Set the background back to its original color here.
}

如果您需要表单继续“迪斯科”直到再次按下按钮，则可以将其包装在while循环中，该循环将一直持续到按下Button为止，或选中ToggleButton。

如果您选择这条路线，建议您阅读asynchronous programming documentation。这非常有帮助。

Answer 2

此代码适用于mi，并且每5秒钟更改“后退”颜色：

    public partial class Form1 : Form
        {
            /// 
            /// a list of colors to control the sequence
            /// 

        Color[] colorsList = { Color.Coral, Color.AliceBlue, Color.DarkRed, Color.Red, Color.Blue, Color.Aquamarine };

        /// <summary>
        /// Timer to control the execution time of the color change
        /// </summary>
        System.Timers.Timer myTimer = new System.Timers.Timer();
        public Form1()
        {
            InitializeComponent();
        }

        /// <summary>
        /// Load or Main of class
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Form1_Load(object sender, EventArgs e)
        {
            this.BackColor = colorsList[0];
            myTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
            myTimer.Interval = 5000;
            myTimer.Start();
        }

        /// <summary>
        /// method that changes the color, executed by the timer
        /// </summary>
        /// <param name="source"></param>
        /// <param name="e"></param>
        private void OnTimedEvent(object source, ElapsedEventArgs e)
        {            
            for (int i = 0; i < colorsList.Length; i++)
            {
                if (this.BackColor == colorsList[i])
                {
                    if (i < colorsList.Length - 1)
                    {
                        this.BackColor = colorsList[i + 1];
                        break;
                    }
                    else
                    {
                        //return to the first color
                        this.BackColor = colorsList[0];
                        break;
                    }
                }
            }
        }
    }

如何降低for循环的速度，以便可以看到颜色？

2 个答案: