Question

我试图在数据网格视图中获取数据。如果我使用此查询，此代码可以正常工作： - “select * from employee.transaction”

但是当我试图把条件放在它没有给出任何输出时（只显示一张空白表）

我的表有使用mysql server 5.6.25的Int.Im类型的月，年列

我无法找到我的代码问题。请提前帮助.Thx。

private void load_data_Click(object sender, EventArgs e)
        {


            string constring = "datasource = localhost;port = 3306;username = ****;password = ****";
            MySqlConnection conDataBase = new MySqlConnection(constring);
            var cmdDataBase = conDataBase.CreateCommand();

            cmdDataBase.CommandText = @"select * from employee.transaction where department = @department AND month = @month AND year = @year";
            cmdDataBase.Parameters.AddWithValue("@department", this.department.Text);
            cmdDataBase.Parameters.AddWithValue("@month", this.dateTimePicker1.Value.Month);
            cmdDataBase.Parameters.AddWithValue("@year", this.dateTimePicker1.Value.Year);
         try
            {
         // here im trying to show table in datagrid view
               MySqlDataAdapter sda = new MySqlDataAdapter();
                sda.SelectCommand = cmdDataBase;
                DataTable dbdataset = new DataTable();
                sda.Fill(dbdataset);
                BindingSource bSource = new BindingSource();

                bSource.DataSource = dbdataset;
                dataGridView1.DataSource = bSource;
                sda.Update(dbdataset);

        //here im trying to make a excel file which would contain what is currently being displayed in the datagrid view
                DataSet ds = new DataSet("New_DataSet");
                DataTable dt = new DataTable("New_DataTable");
                dt.Locale = System.Threading.Thread.CurrentThread.CurrentCulture;
                ds.Locale = System.Threading.Thread.CurrentThread.CurrentCulture;
                ds.Tables.Add(dbdataset);
                ExcelLibrary.DataSetHelper.CreateWorkbook("MyExcelFile.xls", ds);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

Answer 1

问题可能是@ Bjorn-Roger在评论中提到的，'月'和'年'都是SQL中的关键词。

我建议你试试：

select * from employee.transaction where department = @department AND [month] = @month AND [year] = @year

P.S：注意[]使用字段'month'和'year'。

修改1

此外，您可能想要检查输入字段“month”和“year”的日期格式是否与数据库表字段的日期格式相同。

数据网格视图不显示来自mysql表的数据

1 个答案: