填充COMBOX與第一項

Question

我用下面的技術用於填充在WinForms的組合框：

var customer = (new Customer[] { new Customer { CustomerID = -1, CustomerRef = "[Please Select]" } }).Concat(
    from c in ctx.Customers 
    orderby c.CustomerRef ascending 
    select c).ToList(); 

cboCustomerRef.DataSource = customer; 
cboCustomerRef.ValueMember = "CustomerID"; 
cboCustomerRef.DisplayMember = "CustomerRef"; 

是否可以達到同樣的效果，但只有選擇的兩個相關的列（CustomerID和CustomerRef ）而不是所有欄目。

有沒有更好的方法來做到這一點？

謝謝...

Answer 1

試試這個

var customers = 
    from c in ctx.Customers 
    orderby c.CustomerRef ascending 
    select new { CustomerId = c.CustomerID, CustomerRef = c.CustomerRef }).ToList(); 

customers.Insert(0, new { CustomerID = -1, CustomerRef = "[Please Select]"}); 

cboCustomerRef.DataSource = customers; 
cboCustomerRef.ValueMember = "CustomerID"; 
cboCustomerRef.DisplayMember = "CustomerRef"; 

Answer 2

您可以使用下拉事件來檢索您的數據，使 組合框

Customers.Text = [請選擇]

默認情況下。