复选框事件处理

Question

我有一个 MyControl 类。 MyClass 对象内部有文本框和复选框。

我正在尝试添加一个复选框事件处理程序，但它不起作用。可能是什么问题？

private List<MyControls> _myControls = new List<MyControls>();
MyControls mc = new MyControls();

public void CreateFormElements(int i, StringReader sr)
{
    ProductForm form2 = new ProductForm();
    form2.Visible = true;
    form2.Activate();
    String line = "";

    for (int n = 0; n < i; n++)
    {
        line = sr.ReadLine();
        mc = new MyControls();

        if (line.Length > 3)
        {
            String[] _line = line.Split(new char[] { '\t' });
            mc.SetY(30 + n * 20);
            mc.initElements(_line, n);
            _myControls.Add(mc);
            **mc.cb.CheckedChanged += cb_CheckedChanged;**
        }
    }
}


private void cb_CheckedChanged(Object sender, EventArgs e)
{
    string NameSet  = (sender as CheckBox).Name.Split(new char[]{'_'})[1];
    MessageBox.Show(NameSet);
}

这是 MyControls 类的代码：

class MyControls
{
    int x=5;
    int y=30;
    public CheckBox cb = new CheckBox();
    public TextBox tb1 = new TextBox();

    public TextBox tbSpecs = new TextBox();
    public TextBox tb3 = new TextBox();
    public TextBox tb4 = new TextBox();

    public void initElements(String[] name, int i)
    {
        cb.Width = 10;
        cb.Height = 10;
        cb.Name = "cb_" + i.ToString();
        cb.Location = new Point(x, y+5);
        cb.Checked = false;
        Form.ActiveForm.Controls.Add(cb);

        x += 15;

        tb1.Width = 50;
        tb1.Height = 20;
        tb1.Location = new Point(x, y);
        tb1.Name = "tb1_" + i.ToString();
        tb1.Text = name[0];
        Form.ActiveForm.Controls.Add(tb1);
        x += 60;

        tbSpecs.Width = 150;
        tbSpecs.Height = 20;
        tbSpecs.Name = "tb2_" + i.ToString();
        tbSpecs.Text = name[1];
        tbSpecs.Location = new Point(x, y);
        Form.ActiveForm.Controls.Add(tbSpecs);
        x += 160;

        tb3.Width = 40;
        tb3.Height = 20;
        tb3.Name = "tb3_" + i.ToString();
        tb3.Text = name[2];
        tb3.Location = new Point(x, y);
        Form.ActiveForm.Controls.Add(tb3);
        x += 50;

        tb4.Width = 450;
        tb4.Height = 20;
        tb4.Name = "tb4_" + i.ToString();
        tb4.Text = name[3];
        tb4.Location = new Point(x, y);
        Form.ActiveForm.Controls.Add(tb4);

        x = 0;
    }

    public int SetX(int X)
    {
        x = X;
        return x;
    }

    public int SetY(int Y)
    {
        y = Y;
        return y;
    }
}

Answer 1

mc.cb.CheckedChanged += new System.EventHandler(this.cb_CheckedChanged)

Answer 2

CreateFormElements(int i, StringReader sr){...} 中需要检查的几点：

i 是否大于零？如果不是，循环将永远不会运行，并且事件处理程序将永远不会附加。

line.Length 是否大于零？否则，您将永远无法进入 if 块，并且处理程序也不会被附加。