private void button1_Click(object sender, EventArgs e)
        {
            string voc = comboBox1.Text.ToString();

            try
            {
                //performTranslate(comboBox1.SelectedItem.ToString());
                richTextBox2.Text = FormMain.AddWordToMemory(voc);
                if (richTextBox2.Text != "")
                {
                    string webUrl   = "http://media.shanbay.com/audio/us/" + voc + ".mp3";
                    bool   judgeSuc = GetWebPr.getpron(webUrl, config.mp3_dir);
                    if (judgeSuc == true)
                    {
                        button7.Visible = true;
                    }
                    button1.Visible = false;
                    button3.Visible = true;
                    label5.Visible  = true;
                    button3.Focus();
                }
                else
                {
                    throw new Exception();
                }
            }
            catch (Exception)
            {
                MessageBox.Show("请选择需要翻译的单词");
            }
        }
        private void button2_Click(object sender, EventArgs e)
        {
            string voc;

            if (richTextBox1.Text == "")
            {
                MessageBox.Show("请输入单词");
            }
            else
            {
                voc = richTextBox1.Text;
                richTextBox2.Text = FormMain.AddWordToMemory(voc);
                string webUrl   = "http://media.shanbay.com/audio/us/" + voc + ".mp3";
                bool   judgeSuc = GetWebPr.getpron(webUrl, config.mp3_dir);
                if (judgeSuc == true)
                {
                    button6.Visible = true;
                }
                button4.Visible = true;
                button2.Visible = false;
                label3.Visible  = true;
                button4.Focus();
            }
        }