引用dll

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;
using dlltest;
namespace yindlltest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int a, b,c;
            a = Convert.ToInt32(this.textBox1.Text);
            b = Convert.ToInt32(this.textBox2.Text);
            c = Class1.sum(a, b);
            this.label3.Text = c.ToString();
        }
    }
}

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace dlltest
{
    public  class Class1
    {
        public static int sum(int i, int j)
        {
            return i + j;
        }
    }
}

把一些共同的方法编译到dll中，这样可以屏蔽一些代码。