多列组合框

Question

I've read that combo boxes cannot have multiple columns. Which leaves me a bit stuck since what I want to do is display one field from a table, but return the corresponding value from a second field in the same table ie

I'd like to show CustomerNames in the combo box, but when the user selects a name, the CustomerID field is returned instead. Whats the best work around for this?

Answer 1

Best way is to use ComboBoxes DisplayMember and ValueMember properties

set the ComboBox.DisplayMember to the property you want to display. Use ValueMember for property you want to return. Then you can use the ComboBox.SelectedValue to get the current/selected ValueMember

Answer 2

ComboBoxItem的值不必与Text相同，请考虑使用ID作为值。

Answer 3

You don't need multiple columns to implement it.

class Member
{
    public string Name{get;set;}
    public string Address{get;set;}
    public int ID{get;set;}

    public string Description
    {
        get
        {
            return string.Format("{0}, {1}", Name, Address);
        }
    }
}

var members = new []
{
   new Member(){ID = 1, Name = "John", Address = "Addr 1"},
   new Member(){ID = 2, Name = "Mary", Address = "Addr 2"}
};

m_ComboBox.DataSource = members;
m_ComboBox.DisplayMember = "Description"
m_ComboBox.ValueMember = "ID";

now you can access seleceted ID

var selectedID = m_ComboBox.CelectedValue();

Answer 4

您可以通过将ComboBox的DisplayMember和ValueMember属性分别设置为"CustomerName"和"CustomerID"来实现所需的行为。

Answer 5

Take a look at the ValueMember property. You should set this to CustomerID. After you bind to your combobox, the actual field displayed to the user will be the CustomerName, but when you want to get the value of 'CustomerName', it will return the CustomerID.

When you want to get the value of the combobox, simply reference the SelectedValue .

If you are adamant about displaying both of these in the combobox, there are some hackish ways of doing this but I would recommend reviewing your requirements again and seeing if it is absolutely necessary.

Answer 6

Alternatively, you can define KeyValuePair objects with your intended Ids and text fields. Feed them to the combo, since its Items property is a collection of objects. Then, for retrieval use a cast like

var x = (KeyValuePair)combo.Items[0];

and then acces then Key and Value properties of x.

Answer 7

您可以使用ComboBoxItem的Tag属性存储值。