Winform练习题

计算器

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private void button1_Click(object sender, EventArgs e)
        {
            int a = Convert.ToInt32(this.textBox1.Text.Trim());
            int b = Convert.ToInt32(this.textBox2.Text.Trim());
            string c=this.textBox3.Text.Trim();
            int d = 0;
            switch(c)
            {
                case"+":
                    d = a + b;
                    break;
                case"-":
                    d = a - b;
                    break;
                case"*":
                    d = a * b;
                    break;
                case"/":
                    d = a / b;
                    break;
            }
            textBox4.Text = d.ToString();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            string str1 = textBox1.Text;
            string str2 = textBox2.Text;
            int i, j, k;
            if(!int.TryParse(str1,out i ))
            {
                MessageBox.Show("第一个数字不合法");
                return;
            }
            if(int.TryParse(str2,out j)==false)
            {
                MessageBox.Show("第二个数字不合法");
                return;
            }
            k = i + j;
            textBox4.Text = Convert.ToString(k);
        }
    }
}