C#数据库连接与CRUD操作详解

c# 数据库连接和操作大全.txt wxh zt



一：数据库连接代码：
SqlConnection objSqlConnection = new SqlConnection ("server = 127.0.0.1;uid = sa; pwd =;database =test");
objSqlConnection.Open();
二：数据库的添加记录代码：
            int i = 0;
          string s1 = "", s2 = "";
          i = Convert.ToInt16(textBox1.Text);
              s1 = textBox2.Text;
          s2 = textBox3.Text;

            SqlConnection objSqlConnection = new SqlConnection("server = 127.0.0.1;uid = sa; pwd =;database =test");
            objSqlConnection.Open();
            
            MessageBox.Show("数据库连接成功", "好");

               try
               {
                  SqlCommand sqlcom = new SqlCommand("insert into info(id,name,sex) values( " + i + ",'" + s1 + "','" + s2 + "')", objSqlConnection);
                  sqlcom.ExecuteNonQuery();
                   MessageBox.Show("添加成功！", "啊");
               }
              catch (Exception a)
               {
                   MessageBox.Show(a.ToString());
               }
            MessageBox.Show("添加成功！", "啊");

}

三：数据库的修改代码：
            int i = 0;
            string s1 = "", s2 = "";
            s1 = textBox2.Text;
            s2 = textBox3.Text;
            if (textBox1.Text.Length == 0)
                i = 0;
            else
                i = Convert.ToInt32(textBox1.Text);

            SqlConnection objSqlConnection = new SqlConnection("server = 127.0.0.1;uid = sa; pwd =;database =test");
            objSqlConnection.Open();
            MessageBox.Show("数据库连接成功", "好");
            try
            {
                SqlCommand sqlcom = new SqlCommand("update info set name='"+s1+"',sex='"+s2+"'"+"where id=" + i, objSqlConnection);
                sqlcom.ExecuteNonQuery();
                MessageBox.Show("修改成功！", "啊");
                objSqlConnection.Close();
            }
            catch (Exception a)
            {
                MessageBox.Show(a.ToString());
            }
四：数据库的删除代码：
            int i = 0;
            string s1 = "", s2 = "";
            s1 = textBox2.Text;