从datagridview值中删除数据库中的行

Posted 2023-05-08

【中文标题】从datagridview值中删除数据库中的行

【英文标题】：Deleting row from database from datagridview value

【发布时间】：2014-06-29 23:55:47

【问题描述】：

我有一个未绑定的 DataGridView，它显示在前一个表单上选择的 DataTable 数据。如果我想从 DataGridView 中删除一个 DataRow，我希望它更新 DataBase。我有一些代码，但它不能正常工作，它只是删除第一行，而不是删除选定的行（因为它的值我想删除它）。有没有办法获取单元格值并通过查询将其从 DateBase 中删除？我正在使用 SqlCe 3.5

private void removeBTN_Click(object sender, EventArgs e)
    


            string tableName = Data["Quotation Name"].ToString().Trim(); //gets the table name 
            if (MessageBox.Show("Are you sure you want to remove this item? ", "Confirm Delete", MessageBoxButtons.YesNo) == DialogResult.Yes)
               for (int i = 0; i < dataGridView1.Rows.Count - 0; i++)

                string constring = @"Data Source=|DataDirectory|\LWADataBase.sdf";
                string Query = "delete from [" + tableName + "] where [Item Name] = @item ";
                SqlCeConnection conDataBase = new SqlCeConnection(constring);
                SqlCeCommand cmd = new SqlCeCommand(Query, conDataBase);
                cmd.Parameters.Add("@item", dataGridView1.Rows[i].Cells[0].Value.ToString());
                try
                

                    conDataBase.Open();
                    cmd.ExecuteNonQuery();



                    //displays a system error message if a problem is found
                
                catch (Exception ex)
                
                    MessageBox.Show(ex.Message);

                
                getTable(); //loads the table into the DGV



            
        
    

【参考方案1】：

private void removeBTN_Click(object sender, EventArgs e)
    

        string tableName = Data["Quotation Name"].ToString().Trim(); //gets the table name 
        if (MessageBox.Show("Are you sure you want to remove this item? ", "Confirm Delete", MessageBoxButtons.YesNo) == DialogResult.Yes)
        

            foreach (DataGridViewRow r in quotation_NameDataGridView.SelectedRows)
            

                string constring = @"Data Source=|DataDirectory|\LWADataBase.sdf";
                string Query = "delete from [" + tableName + "] where [Item Name] like @item";
                SqlCeConnection conDataBase = new SqlCeConnection(constring);
                SqlCeCommand cmd = new SqlCeCommand(Query, conDataBase);
                if (r.Cells[0] != null)
                

                    cmd.Parameters.Add("@item", r.Cells[0].Value.ToString());

                    try
                    
                        conDataBase.Open();
                        int res = cmd.ExecuteNonQuery();
                        conDataBase.Close();
                        //displays a system error message if a problem is found
                    
                    catch (Exception ex)
                    
                        MessageBox.Show(ex.Message);

                    
                
                getTable(); //loads the table into the DGV

            
        
    

【讨论】：

@user3521452 更新了答案，参数必须用单引号括起来'

谢谢哥们，我看看怎么样。

单击按钮时仍然没有任何反应

@user3521452 更新答案，忘记单引号，加个if避免空引用异常并关闭连接

@user3521452 您可以将datagridview的SelectionMode属性设置为FullRowSelect