一个接一个地改变标签的颜色

Question

I have a window with some labels. I want the BackColor of the labels to change depending of some tests I am running:

private void btnStartTest_Click(object sender, EventArgs e)
    {
        if(Tests.FirstTest())
        {
            this.lblFirstTest.BackColor = Color.LawnGreen;
        }
        else
        {
            this.lblFirstTest.BackColor = Color.Red;
        }

        if(Tests.SecondTest())
        {
            this.lblSecondTest.BackColor = Color.LawnGreen;
        }
        else
        {
            this.lblSecondTest.BackColor = Color.Red;
        }

        //and so on...
    }

I want the labels to change color one after another to show progress. But right now the color change only takes effect at the end of the method. So all labels change color at the same time.

Why is this? And what can I change to get the desired effect?

Answer 1

Perform a Refresh on the form after each colour change. That should force visual elements to be updated and redrawn, giving the desired effect. This is the simplest way that does not involve threading.

Answer 2

就像BugFinder所说的那样......在不同的线程上运行该方法（Task.RunAsync（（）=> {}））...但是在这种情况下你必须使用一个调度程序来为控件赋值（或者别的例外）