在C#中如何点击按钮可更换pictureBox里的图片

Question

在C#中在textbox上输入一个数，点击按钮，根据数的范围，更换pictureBox里的图片

private void button1_Click(object sender, EventArgs e)
        {
            int ts = Convert.ToInt32(txttanshang.Text);
            if (0<ts<120)
            {
                pictureBox1.BackgroundImage = WindowsFormsApplication2.Properties.Resources.BG1;
                pictureBox1.BackgroundImageLayout = ImageLayout.Stretch;
            }
            else if (120 <= ts < 240)
            {
                pictureBox1.BackgroundImage = WindowsFormsApplication2.Properties.Resources.BG1;
                pictureBox1.BackgroundImageLayout = ImageLayout.Stretch;
            }
            else if (240 <= ts < 360)
            {
                pictureBox1.BackgroundImage = WindowsFormsApplication2.Properties.Resources.BG1;
                pictureBox1.BackgroundImageLayout = ImageLayout.Stretch;
            }
            else if (360 <= ts)
            {
                pictureBox1.BackgroundImage = WindowsFormsApplication2.Properties.Resources.BG1;
                pictureBox1.BackgroundImageLayout = ImageLayout.Stretch;
            }

        }

如何处理 if (0<ts<120)处显示小于号无法处理bool和int类的操作

Answer 1

 if (0<ts<120)
不能这么写
应该是
 if (0<ts  && ts<120)