列表.添加不增加的List.Count

我正试图将元素添加到List<String>，以便我可以一次从队列中删除它们。下面是添加东西到我的列表的代码:

foreach (String s in q)
{
    if(s != null)
    {
        String str = s.Replace("!question", "");
        questions.Add(str);
        this.label1.Text = str;
    }
}

q是我用来分割的数组，questions是一个List<String>。Label1应该是不相关的(我使用Windows窗体)

这是我用来尝试从列表中删除第二行的代码。它抛出一个'out of range'异常:

questions.RemoveAt(1);
Console.WriteLine(questions.Count);
foreach(String s in questions)
{
    if (s!= null)
        this.label1.Text = s;
}

当它打印到控制台时，Count是1，但如果我打印列表，它会给我正确的列表:

test 1
test 2
test 3 
....

我的假设是，我所有的字符串被添加到列表下的第一个索引与返回字符，但我不太确定它是如何工作的。谢谢大家!

EDIT: Input .txt:

test 1 't
test 2 't
cellosan asks: !question are we getting secret stream? 't
cellosan asks: !question read chat pls 't
cellosan asks: !question sorry for bothering you too 't

EDIT: 完整代码

namespace Question_Queue
{
    public partial class Form1 : Form
    {
        public String fullText;
        public String[] questionList;
        public List<String> questions;
        public int i = 0;
        public String[] q;
        public Form1()
        {
            InitializeComponent();
            questionList = new String[20];
            q = new String[30];
            questions = new List<String>(20);
        }
        private void Form1_Load(object sender, EventArgs e)
        {
        }
        //This is the refresh button
        private void button1_Click(object sender, EventArgs e)
        {
            using (FileStream fs = File.Open("C:''Users''Lilianne''Desktop''questions.txt", FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
            {
                using(StreamReader questionDoc = new StreamReader(fs))
                {
                    //Now we have the stuff in question doc.  Let's make an array for all the questions
                    if (questionDoc.ReadLine() != null)
                    {
                        fullText = questionDoc.ReadToEnd();
                        questionList = fullText.Split(''t');
                        for (int j = 0; j < questionList.Length; j++)
                        {
                            questionList[j] = questionList[j].Replace("!question", "");
                            questionList[j] = questionList[j].Replace("'t", "");
                            this.label1.Text = questionList[j];
                        }
                    }
                    else
                        this.label1.Text = "No questions!";
                    questionDoc.Close();
                }
            }
        }
        private void Answered_Click(object sender, EventArgs e)
        {
            using (FileStream fs = File.Open("C:''Users''Lilianne''Desktop''questions.txt", FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite))
            {
                using(StreamReader sr = new StreamReader(fs))
                {
                    //First, remove the topmost question, which is the second line
                    Console.WriteLine(questions.Count);
                    //questions.RemoveAt(2);
                    foreach(String s in questions)
                    {
                        if (s!= null)
                            this.label1.Text = s;
                    }
                }
            }
        }

        private void ClearQueue_Click(object sender, EventArgs e)
        {
            File.WriteAllText("C:''Users''Lilianne''Desktop''questions.txt", "***** EMPTY LINE *****");
        }
        private void Load_Click(object sender, EventArgs e)
        {
        }
        private void button1_Click_2(object sender, EventArgs e)
        {
            using (FileStream fs = File.Open("C:''Users''Lilianne''Desktop''questions.txt", FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
            {
                using (StreamReader sr = new StreamReader(fs))
                {
                    if (sr.ReadLine() != null)
                    {
                        fullText = sr.ReadToEnd();
                        q = fullText.Split(''t');

                        foreach (String s in q)
                        {
                            if(s != null)
                            {
                                String str = s.Replace("!question", "");
                                questions.Add(str);
                                this.label1.Text = str;
                            }
                        }
                    }
                }
            }
        }
    }
}