C#数据库操作 附：代码实例说明.doc

C#数据库连接操作大全一：数据库连接代码：SqlConnection objSqlConnection = new SqlConnection (server = ;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 = ;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;elsei = Convert.ToInt32(textBox1.Text);SqlConnection objSqlConnection = new SqlConnection(server = ;uid = sa; pwd =;database =test);objSqlConnection.Open();MessageBox.Show(数据库连接成功, 好);trySqlCommand 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;s2 = textBox3.Text;if(textBox1.Text.Length=0)i=0;else i = Convert.ToInt16(textBox1.Text);SqlConnection objSqlConnection = new SqlConnection(server = ;uid = sa; pwd =;database =test);objSqlConnection.Open();MessageBox.Show(数据库连接成功, 好);trySqlCommand sqlcom = new SqlCommand(delete from info where id=+i, objSqlConnection);sqlcom.ExecuteNonQuery();MessageBox.Show(删除成功！, 啊);objSqlConnection.Close();catch (Exception a)MessageBox.Show(a.ToString();五：数据库的查询代码：1.类开始：DataTable dt1 = new DataTable();SqlDataAdapter da1 = new SqlDataAdapter();2.按钮代码：int i = 0,n=0;string s1 = , s2 = ;s1 = textBox2.Text;s2 = textBox3.Text; if (textBox1.Text.Length = 0)i = 0;elsei = Convert.ToInt32(textBox1.Text);SqlConnection objSqlConnection = new SqlConnection(server = ;uid = sa; pwd =;database =test);objSqlConnection.Open();MessageBox.Show(数据库连接成功, 好);string query = SELECT * from info where id=+i;DataSet objDataSet = new DataSet();SqlDataAdapter obj = new SqlDataAdapter();obj.SelectCommand = new SqlCommand(query, objSqlConnection);obj.Fill(objDataSet, info);SqlCommand objSqlCommand = new SqlCommand(query, objSqlConnection);SqlDataReader objSqlReader = objSqlCommand.ExecuteReader(); while (objSqlReader.Read()n += 1;MessageBox.Show(编号: + objSqlReader.Getvalue(0) + 姓名: + objSqlReader.Getvalue(1) + 性别 + objSqlReader.Getvalue(2);if (n = 0)MessageBox.Show(数据库中没有这样的记录！);六：数据库的查询代码： int i = 0; / int n = 0;string s1 = , s2 = ;string sql;s1 = textBox2.Text;s2 = textBox3.Text;if (textBox1.Text.Length = 0)i = 0;elsei = Convert.ToInt32(textBox1.Text); SqlConnection objSqlConnection = new SqlConnection(server = ;uid = sa; pwd =;database =test);objSqlConnection.Open();MessageBox.Show(数据库连接成功, 好);string query = SELECT * from info where id=+i;if(i=0)sql = select * from info ;elsesql = select * from info where id= + i;da1 = new SqlDataAdapter(sql, objSqlConnection);dt1.Clear();da1.Fill(dt1);dataGridView1.DataSource = dt1;数据库的封装类代码：class DBClasspublic void dbclass(stringsql)trySqlConnection sqlcon = new SqlConnection(server = ;uid = sa; pwd =;database =test);sqlcon.Open();SqlTransaction objt = sqlcon.BeginTransaction();/事物开始SqlCommand sqlcom = new SqlCommand(sql, sqlcon);sqlcom.Transaction = objt; /将Command 对象设置为事物处理的对象sqlcom.ExecuteNonQuery();objt.Commit(); /提交事物sqlcon.Close();catch (Exception a)MessageBox.Show(a.ToString();-db2 数据库连接代码： string strcon = Provider = IBMDADB2; Data Source=hfzd;User Id=db2admin;Password=db2admin;/string sql = select * from ADMINISTRATOR.HFZD;string sql = delete from ADMINISTRATOR.HFZD where ID=1