Question

我想创建一个切换按钮，但它仍处于打开状态。如何将按钮从开启切换到关闭。

private void Form2_Load(object sender, EventArgs e){ 

    Button button = new Button();
    button.Location = new Point(200, 30);
    button.Text = "Off";
    this.Controls.Add(button);

    if (button.Text != "On")
    {
        button.Text = "On";
        button.BackColor = Color.Green;
    }
    else if (button.Text == "On")
    {
        button.Text = "On";
        button.BackColor = Color.Red;
    }
}

Answer 1

您需要输入代码以更改按钮在该按钮的Click事件处理程序中的外观：

private void Form2_Load(object sender, EventArgs e){ 

    Button button = new Button();
    button.Location = new Point(200, 30);
    button.Text = "Off";
    this.Controls.Add(button);

    // subscribe to the Click event
    button.Click += button_Click;
}

// the Click handler
private void button_Click(object sender, EventArgs e)
{
    Button button = sender as Button;
    if (button == null) return;

    if (button.Text != "On")
    {
        button.Text = "On";
        button.BackColor = Color.Green;
    }
    else if (button.Text == "On")
    {
        button.Text = "Off";
        button.BackColor = Color.Red;
    }
}

请注意，在else块中，您设置了错误的文字。将其更改为"Off"。

Answer 2

您始终将文字设置为On。更改你的其他块：

else if (button.Text == "On")
{
    button.Text = "Off"; // here !!!
    button.BackColor = Color.Red;
}

或者使用此解决方案创建ToggleButton： ToggleButton in C# WinForms

Answer 3

应该是这样的：点击时创建 + 更改状态：

  private void Form2_Load(object sender, EventArgs e){ 
    // Initial creation
    Button button = new Button() {
      Location = new Point(200, 30),
      Text = "Off",
      BackColor = Color.Red,  
      Parent = this,
    };

    // Click handle, let it be lambda
    // Toggle on click (when clicked change On -> Off -> On ...)
    button.Click += (s, ev) => {
      Button b = sender as Button;

      if (b.Text == "On") {
        // when "On" change to "Off"
        b.Text = "Off";
        b.BackColor = Color.Red;
      }
      else {
        b.Text = "On";
        b.BackColor = Color.Green;
      } 
    };
  }

on off按钮停留在On

3 个答案: