C#之MySql更新

2019-11-11 06:16:25

字體：大中小

來源：轉載

供稿：網友

1.接著前面的往下做，主要邏輯：當雙擊某一行時，右側的文本框和單選按鈕將會顯示對應的值，添加按鈕將會變成【修改】。UserForm中添加事件

PRivate void dataGridView1_CellDoubleClick(object sender, DataGridViewCellEventArgs e) { //雙擊一行，給對應文本框賦值 // 獲取雙擊的行 var currentRow=dataGridView1.Rows[e.RowIndex]; tbUserNo.Text = currentRow.Cells[0].Value.ToString(); tbUserName.Text = currentRow.Cells[1].Value.ToString(); tbUserPwd.Text = currentRow.Cells[2].Value.ToString(); if (currentRow.Cells[3].Value.ToString() == "1") { rbClerk.Checked = true; } else { rbManager.Checked = true; } btnAdd.Text = "修改"; // tbUserName.ReadOnly = true; }

這里寫圖片描述

2.和之前一樣，更新操作不返回任何數據，我們只需要一個標識以確認是否更新，sqlHelper可以重用一個函數。sqlHelper類庫中添加

public static int update(string sql, params MySQLParameter[] ps) { using (MySqlConnection myCon = new MySqlConnection(conStr)) { MySqlCommand cmd = new MySqlCommand(sql, myCon); cmd.Parameters.AddRange(ps); myCon.Open(); return cmd.ExecuteNonQuery(); } }

3.在UserForm中添加一個update方法，返回一個bool值，為true的話則修改成功。同時對添加按鈕觸發的事件進行更改。如果按鈕的文本值是【添加】則進行新增操作，若是【修改】則進行更新操作，調用update方法。

private bool update(User u) { string sql = "update user set user_name=@uName,user_pwd=@uPwd,type=@uType where user_no=@uNo"; MySqlParameter[] list ={ new MySqlParameter("@uName", u.user_name), new MySqlParameter("@uPwd", u.user_pwd), new MySqlParameter("@uType", u.type), new MySqlParameter("@uNo", u.user_no) }; //第二種寫法 /*List<MySqlParameter> list = new List<MySqlParameter>(); list.Add(new MySqlParameter("@uName", u.user_name)); list.Add(new MySqlParameter("@uPwd", u.user_pwd)); list.Add(new MySqlParameter("@uType", u.type)); list.Add(new MySqlParameter("@uNo", u.user_no)); return SqlHelper.helper.update(sql, list.ToArray())>0; */ return SqlHelper.helper.update(sql, list)>0; }private void btnAdd_Click(object sender, EventArgs e) { if (btnAdd.Text == "添加") { User user = new User() { user_name = tbUserName.Text, user_pwd = tbUserPwd.Text, type = rbClerk.Checked ? 1 : 0 }; if (AddUser(user)) { LoadUser(); MessageBox.Show("新增成功"); } else { MessageBox.Show("新增失敗，請重新嘗試"); } this.tbUserName.Text = this.tbUserPwd.Text = string.Empty; this.rbClerk.Checked = this.rbManager.Checked = false; } else { User user = new User() { user_no=Convert.ToInt32(tbUserNo.Text), user_name = tbUserName.Text, user_pwd = tbUserPwd.Text, type = rbClerk.Checked ? 1 : 0 }; if (update(user)) { MessageBox.Show("修改成功"); btnClear_Click(null, null); LoadUser(); } else { MessageBox.Show("修改失敗"); } } }