聯手英偉達，網魚網咖計劃年內開出 30 家電競酒店
阿新 • • 發佈：2021-07-12
dapper的使用
安裝
控制檯中安裝
Install-Package Dapper
方法 ：Execute
返回: 受影響的行數
執行: 刪 改 查
引數:
Execute(sql, //查詢語句
param, // default = null 引數
transaction, //default = null 事務
commandTimeout, //default = null 最大連線時間
commandType //default = null 命令型別？
)
程式碼：
/// <summary> /// Execute插入一條 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button1_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { Person person = new Person("zhangsan","[email protected]","3212151343","男"); string sqlstr = "INSERT INTO person(name,email,gender,phone) VALUES(@name,@email,@gender,@phone) "; int affectedRows = conn.Execute(sqlstr, person, null, null); textBox1.Text = affectedRows.ToString(); } } /// <summary> /// Execute插入多條 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button2_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { List<Person> personList = new List<Person>(); personList.Add(new Person("zhangsan", "[email protected]", "3212151343", "男")); personList.Add(new Person("zhsffa", "[email protected]", "31511511543", "男")); string sqlstr = "INSERT INTO person(name,email,gender,phone) VALUES(@name,@email,@gender,@phone) "; int affectedRows = conn.Execute(sqlstr, personList, null, null); textBox1.Text = affectedRows.ToString(); } } /// <summary> /// Execute 更新一條 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button3_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { Person person = new Person(); person.Id = 15; person.Gender = "改改看"; string sqlstr = "UPDATE person SET gender = @gender WHERE id = @id "; int affectedRows = conn.Execute(sqlstr, person, null, null); textBox1.Text = affectedRows.ToString(); } } /// <summary> /// Execute 更新多條 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button4_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { List<Person> personList = new List<Person>(); personList.Add(new Person(3,"", "", "3212151343", "^-^")); personList.Add(new Person(5,"zhsffa", "[email protected]", "31511511543", "^0^")); string sqlstr = "UPDATE person SET gender = @gender WHERE id = @id "; int affectedRows = conn.Execute(sqlstr, personList, null, null); textBox1.Text = affectedRows.ToString(); } } /// <summary> /// Execute 刪除一條 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button5_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { string sqlstr = "DELETE FROM person WHERE id = @id "; int affectedRows = conn.Execute(sqlstr, new { id = 9}, null, null); textBox1.Text = affectedRows.ToString(); } }
方法 ：Query
Query QueryFirst QueryFirstOrDefault
返回:對映結果
執行: 匿名 強型別？ 一對一 一對多 多型別？
引數:
Query(sql, //查詢語句
param, // default = null 引數
transaction, //default = null 事務
buffered, //default = null 查詢的緩衝結果？
commandTimeout, //default = null 最大連線時間
commandType //default = null 命令型別？
)
程式碼
/// <summary> /// Query 查詢一條 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button7_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { string sqlstr = "SELECT * FROM person "; Person person = conn.Query<Person>(sqlstr).FirstOrDefault(); textBox1.Text = person.ToString(); } } /// <summary> /// 查詢多條 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button8_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { List<Person> personList = new List<Person>(); string sqlstr = "SELECT * FROM person "; personList = conn.Query<Person>(sqlstr).ToList(); string str = null; foreach (Person person in personList) { str += person.ToString(); } textBox1.Text = str; } } /// <summary> /// Query 一對一查詢 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button9_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { List<Person> personList = new List<Person>(); string sqlstr = "SELECT p.*,r.role_name FROM person p INNER JOIN role r ON p.role_id = r.role_id"; var list = conn.Query<Person, Role, Person>(sqlstr, (person, role) => { person.Role = role; return person; }, null, null, true, splitOn:"role_id" ).ToList(); this.dataGridView1.DataSource = list; } } /// <summary> /// Query 一對多查詢 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button10_Click(object sender, EventArgs e) { // 姑且這麼用，但是很多東西還不明白 比如賦值的過程 using (IDbConnection conn = SqlConnection.MySqlConnection()) { List<Person> personList = new List<Person>(); var lookUp = new Dictionary<int, Person>(); string sqlstr = "SELECT p.* ,r.*,s.* " + "from person_role s " + "left join person p on p.id = s.person_id " + "left join role r on s.role_id = r.role_id"; var list = conn.Query<Person, Role, Person>(sqlstr, (person, role) => { Person p; if (!lookUp.TryGetValue(person.Id,out p)) { lookUp.Add(person.Id, p = person); } person.RoleList.Add(role); return person; }, null, null, true, splitOn:"role_id,id" ).ToList(); this.dataGridView1.DataSource = list; } }
事務
/// <summary> /// 事務 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void button11_Click(object sender, EventArgs e) { using (IDbConnection conn = SqlConnection.MySqlConnection()) { IDbTransaction trans = conn.BeginTransaction(); try { Person person1 = new Person("zhangsan", "[email protected]", "3212151343", "男"); Person person2 = new Person("asdfban", "[email protected]", "87654", "男"); string sqlstr = "INSERT INTO person(name,email,gender,phone) VALUES(@name,@email,@gender,@phone) "; int affectedRows1 = conn.Execute(sqlstr, person1, trans, null); int affectedRows2 = conn.Execute(sqlstr, person2, trans, null); trans.Commit(); textBox1.Text = affectedRows1.ToString() + "---"+ affectedRows2.ToString(); } catch (Exception) { trans.Rollback(); } } }