Question

当我尝试在MainPage构造函数中执行下面的代码时，它完美地运行。但是当我在一些Button_Click方法下放置相同的代码时，它会给我一个错误 - Stack1.Children.Add（shuffleRadio [1]）;

它是一个带有随机选项生成和代码内单选按钮生成的测验。

 private void Button_Click(object sender, RoutedEventArgs e)
    {
        questions = questionset.ToList<String>();
        answers = answerset.ToList<String>();
        try
        {


            tr = randomizer.Next(4);
            que.Text = questions[tr].ToString();
            questions.RemoveAt(tr);

            RadioButton ra1 = new RadioButton();
            ra1.Name = "ans1";
            ra1.Content = answers[tr].ToString();
            ra1.GroupName = "Group1";
            ra1.Checked += RadioButton_Checked;
            answers.RemoveAt(tr);

            RadioButton ra2 = new RadioButton();
            rand = randomizer.Next(5);
            ra2.Name = "ans1";
            ra2.Content = answers[rand].ToString();
            ra2.GroupName = "Group1";
            ra2.Checked += RadioButton_Checked;
            answers.RemoveAt(rand);

            RadioButton ra3 = new RadioButton();
            rand = randomizer.Next(3);
            ra3.Name = "ans1";
            ra3.Content = answers[rand].ToString();
            ra3.GroupName = "Group1";
            ra3.Checked += RadioButton_Checked;
            answers.RemoveAt(rand);

            RadioButton ra4 = new RadioButton();
            rand = randomizer.Next(2);
            ra4.Name = "ans1";
            ra4.Content = answers[rand].ToString();
            ra4.GroupName = "Group1";
            ra4.Checked += RadioButton_Checked;
            answers.RemoveAt(rand);

            List<RadioButton> shuffleRadio = new List<RadioButton>();
            shuffleRadio.Add(ra1);
            shuffleRadio.Add(ra2);
            shuffleRadio.Add(ra3);
            shuffleRadio.Add(ra4);

            Random rng = new Random();
            int r = shuffleRadio.Count;
            while (r > 1)
            {
                r--;
                int tem = rng.Next(r + 1);
                RadioButton value = shuffleRadio[tem];
                shuffleRadio[tem] = shuffleRadio[r];
                shuffleRadio[r] = value;
            }


            Stack1.Children.Add(shuffleRadio[0]);
            Stack1.Children.Add(shuffleRadio[1]);     //The error is here
            Stack1.Children.Add(shuffleRadio[2]);
            Stack1.Children.Add(shuffleRadio[3]);

        }
        catch (Exception erg)
        {
            MessageBox.Show(erg.ToString());
        }
    }

Answer 1

这是因为我在stackpanel中添加的内容与以前的内容重复了

 foreach (var itm in shuffleRadio)
            {
                RadioButton ra = new RadioButton();
                ra.Content = itm.Content.ToString();
                ra.GroupName = "Group1";
                ra.Checked += RadioButton_Checked;
                Stack1.Children.Add(ra);
            }

我尝试在Button_Click方法C＃和XAML中调用它时出现System.Argument.Exception错误

1 个答案: