Question

我正在开发Windows应用程序，其中我绑定了datagridview和textboxes控件。我想从load事件中检索两个不同表中的值。

这意味着存储在一个表中的datagridview值和存储在其他表中的文本框值。我该怎么办？

以下是我的form_load事件代码：

private void Purchase_Load(object sender, EventArgs e)
{
   bindgrid();
}

private void bindgrid()
{
   try
   {
       con.Open();
       SqlCommand cmd = new SqlCommand("select distinct product_id, product_name, qty, price, tax, discount, total from Purchasedetail union all select total from Purchase ", con);
       da.SelectCommand = cmd;
       cmd.ExecuteNonQuery();

       DataSet ds = new DataSet();
       da.Fill(ds, "Purchsedetail");
       da.Fill(ds, "Purchase");

       datagrid.DataSource = ds.Tables[0];
   }
   catch (Exception ex)
   {
       MessageBox.Show("Exception caught : " + ex.Message.ToString());
   }
   finally
   {
      con.Close();
   }
}

Answer 1

您需要用分号分隔两个select命令。（UNION尝试将两个结果集合并到一个结果集中，并且需要有两个具有相同模式的结果集）

try
{
    con.Open();
    string cmdText = @"select distinct product_id, product_name, 
                             qty, price, tax, discount, total 
                             from Purchasedetail;
                       select total from Purchase ";

    SqlCommand cmd = new SqlCommand(cmdText, con); 

    // You pass the command and fill the DataSet. 
    da.SelectCommand = cmd;
    DataSet ds = new DataSet();
    da.Fill(ds);

    // Now the Dataset contains two tables
    datagrid.DataSource = ds.Tables[0];

    // Of course this retrieves just the total from the first row,
    // I suppose that your second query needs some kind of WHERE condition
    // or some kind of aggregate function like SUM(Total) 
    textBox1.Text = ds.Tables[1].Rows[0][0].ToString();
}
catch (Exception ex)
{
    MessageBox.Show("Exception caught : " + ex.Message);
} 
finally
{
   con.Close();
}

如何从表单加载事件中的两个表中检索值

1 个答案: