using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace _2计算器练习 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void button1_Click(object sender, EventArgs e) { string str1 = tb_one.Text; string str2 = tb_two.Text; //判断是否为整数 int i1, i2; if (!int.TryParse(str1, out i1)) { MessageBox.Show("第一个数值不是合法的整数!"); return; } if (!int.TryParse(str2, out i2)) { MessageBox.Show("第二个数值不是合法的整数!"); return; } int sum = i1 + i2; //这里要按整数转换为string类型以后在赋值给tb_sum.Text tb_sum.Text = Convert.ToString(sum); } } }