将文本附加到富文本框的开头

Question

private void button1_Click(object sender, EventArgs e)
{
    richTextBox1.AppendText("\r\n");
    richTextBox1.Focus();
    string s = "Enter ";
    richTextBox1.AppendText(s + "\r\n");
    richTextBox1.SelectionStart = richTextBox1.Text.Length - (s.Length +1);
    richTextBox1.SelectionLength = s.Length +1;
    richTextBox1.SelectionFont = new Font("Arial", 12, FontStyle.Bold);
    richTextBox1.DeselectAll();
    richTextBox1.SelectionStart = richTextBox1.Text.Length;
    richTextBox1.SelectionLength = richTextBox1.Text.Length;
    richTextBox1.SelectionFont = new Font("Arial", 12, FontStyle.Regular);
    richTextBox1.DeselectAll();
}

每次用户点击按钮时,我都希望新的"Enter"位于RichTextBox底部而不是底部.我该怎么做？

Answer 1

从技术上讲,如果你将它插入文本的顶部,你就是"插入"或"前置",而不是"附加".;)

您可以使用SelectedText属性在RichTextBox的开头插入文本.我刚刚敲了一个快速的演示应用来测试它:

    private void button1_Click(object sender, EventArgs e)
    {
        richTextBox1.SelectionStart = 0;
        richTextBox1.SelectionLength = 0;
        richTextBox1.SelectedText = DateTime.Now.ToString();
    }

当单击button1时,将当前时间插入RichTextBox的开头.