private void dgvGroup_RowEnter(object sender, DataGridViewCellEventArgs e)
{
northwindEntities dc = new northwindEntities();
string Country = Convert.ToString(dgvGroup.Rows[e.RowIndex].Cells[0].Value);
var query = from c in dc.Customers
where c.Country == Country
select c;
dgvDetails.DataSource = query.ToList();
}
private void Form1_Load(object sender, EventArgs e)
{
// TODO: 這行程式碼會將資料載入 'northwindDataSet.Customers' 資料表。您可以視需要進行移動或移除。
this.customersTableAdapter.Fill(this.northwindDataSet.Customers);
// TODO: 這行程式碼會將資料載入 'northwindDataSet.Customers' 資料表。您可以視需要進行移動或移除。
this.customersTableAdapter.Fill(this.northwindDataSet.Customers);
//select Country, Count(*) from Customers group by Country
northwindEntities dc = new northwindEntities();
//var query = (from c in dc.Customers
// group c by c.Country into CountryGroup
// select new
// {
// 國家 = CountryGroup.Key,
// 人數 = CountryGroup.Count()
// }).OrderByDescending(group => group.人數);
var query = dc.Customers.GroupBy(c => c.Country).Select(CountryGroup => new
{
家 = CountryGroup.Key,
人數 = CountryGroup.Count()
}).OrderByDescending(g => g.人數);
dgvGroup.DataSource = query.ToList();
}