Question

我试图在VB Forms中找到一种等待命令，但是我不希望使用sleep命令，因为它会在执行所有代码之前冻结程序。有什么办法吗？

TextBox1.Text = "0"
' (Code goes here)
TextBox2.Text = "0"

Answer 1

最简单的答案是使用Async / Await和Task.Delay。

只需执行以下操作：

Private Async Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    TextBox1.Text = "Immediately"
    Await Task.Delay(TimeSpan.FromSeconds(2.0))
    TextBox1.Text = "Later"
End Sub

请注意，我必须将标准Private Sub Button1_Click处理程序签名更改为Private Async Sub Button1_Click。

另一个选择是使用Windows窗体计时器。只需将一个从工具箱拖到您的表单上即可。

然后您可以执行以下操作：

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    TextBox1.Text = "Immediately"
    Timer1.Interval = 2000
    Timer1.Enabled = True
End Sub

Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
    TextBox1.Text = "Later"
End Sub

如果要在更新文本之前停止计时器，可以执行以下操作：

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    Timer1.Enabled = False
    TextBox1.Text = "Stopped"
End Sub

如何在不使用sleep命令的情况下在VB中发出等待命令？

1 个答案: