c# 如何获得textBox控件,提取从开始输入第一个字符到回车的时间差

[emailqjc]

c# 如何获得textBox控件,提取从开始输入第一个字符到回车的时间差

[ken_flash]

onkeydown+={
}

[我姓区不姓区]

        private DateTime time;

        private void textBox1_KeyDown(object sender, KeyEventArgs e)
        {
            if (string.IsNullOrEmpty(textBox1.Text))
            {
                time = DateTime.Now;
            }
            else if (e.KeyCode == Keys.Enter)
            {
                MessageBox.Show((DateTime.Now - time).TotalSeconds.ToString());
            }
        }

[wnyxy001]

        Stopwatch sw = new Stopwatch();   //.net里专门用于计时的类（using System.Diagnostics）
        private void textBox1_TextChanged(object sender, EventArgs e)
        {
            sw.Start();
        }

        private void textBox1_KeyDown(object sender, KeyEventArgs e)
        {
            if(e.KeyCode==Keys.Enter)
            {
                sw.Stop();
                string aa = sw.Elapsed.ToString();
                MessageBox.Show(aa);
            }

        }