如何将列表绑定到组合框? [英] How to bind a List to a ComboBox?

问题描述

我想将 BindingSource 连接到类对象列表，然后将对象值连接到 ComboBox.
谁能建议怎么做?

I want to connect a BindingSource to a list of class objects and then objects value to a ComboBox.
Can anyone suggest how to do it?

public class Country
{
    public string Name { get; set; }
    public IList<City> Cities { get; set; }

    public Country()
    {
        Cities = new List<City>();
    }
}

是我的班级，我想将其 name 字段绑定到一个 BindingSource，然后可以将其与 ComboBox 关联

is my class and I want to bind its name field to a BindingSource which could be then associated with a ComboBox

推荐答案

当您提到组合框时，我假设您不想使用 2 路数据绑定(如果是这样，请查看使用 BindingList)

As you are referring to a combobox, I'm assuming you don't want to use 2-way databinding (if so, look at using a BindingList)

public class Country
{
    public string Name { get; set; }
    public IList<City> Cities { get; set; }
    public Country(string _name)
    {
        Cities = new List<City>();
        Name = _name;
    }
}

List<Country> countries = new List<Country> { new Country("UK"), 
                                     new Country("Australia"), 
                                     new Country("France") };

var bindingSource1 = new BindingSource();
bindingSource1.DataSource = countries;

comboBox1.DataSource = bindingSource1.DataSource;

comboBox1.DisplayMember = "Name";
comboBox1.ValueMember = "Name";

要查找在绑定组合框中选择的国家/地区，您可以执行以下操作:Country country = (Country)comboBox1.SelectedItem;.

To find the country selected in the bound combobox, you would do something like: Country country = (Country)comboBox1.SelectedItem;.

如果您希望 ComboBox 动态更新，您需要确保您设置为 DataSource 的数据结构实现了 IBindingList；一种这样的结构是BindingList.

If you want the ComboBox to dynamically update you'll need to make sure that the data structure that you have set as the DataSource implements IBindingList; one such structure is BindingList<T>.

提示:确保将 DisplayMember 绑定到类上的属性而不是公共字段.如果你的班级使用 public string Name { get;放;} 它将工作，但如果它使用 public string Name; 它将无法访问该值，而是将显示组合框中每一行的对象类型.

Tip: make sure that you are binding the DisplayMember to a Property on the class and not a public field. If you class uses public string Name { get; set; } it will work but if it uses public string Name; it will not be able to access the value and instead will display the object type for each line in the combo box.

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