BindingMode 枚举

定义

命名空间:

Microsoft.Maui.Controls

程序集:

Microsoft.Maui.Controls.dll

Source:

BindingMode.cs

指定绑定中的数据流方向。

public enum class BindingMode

public enum BindingMode

type BindingMode = 

Public Enum BindingMode

继承

Enum

BindingMode

字段

名称	值	说明
Default	0	使用目标属性的默认绑定模式。
TwoWay	1	在任一更改时更新目标和源。
OneWay	2	在源更改时更新目标。
OneWayToSource	3	目标更改时更新源。
OneTime	4	仅在创建绑定时更新目标一次。

注解

以下示例演示了一些 BindingMode 用例。

public class PersonViewModel
{
  public string Name { get; set; }
  public string Company { get; set; }
}

Label label;
PersonViewModel viewmodel;

//BindingMode.OneWay
label = new Label ();
label.BindingContext = viewmodel = new PersonViewModel ();
label.SetBinding<PersonViewModel> (Label.TextProperty, vm => vm.Name, mode: BindingMode.OneWay);

viewmodel.Name = "John Doe";
Debug.WriteLine (label.Text); //prints ""
label.Text = "Foo";
Debug.WriteLine (viewmodel.Name); //prints "John Doe"


//BindingMode.TwoWay
label = new Label ();
label.BindingContext = viewmodel = new PersonViewModel ();
label.SetBinding<PersonViewModel> (Label.TextProperty, vm => vm.Name, mode: BindingMode.TwoWay);

viewmodel.Name = "John Doe";
Debug.WriteLine (label.Text); //prints "John Doe"
label.Text = "Foo";
Debug.WriteLine (viewmodel.Name); //prints "Foo"


//BindingMode.OneWayToSource
label = new Label ();
label.BindingContext = viewmodel = new PersonViewModel ();
label.SetBinding<PersonViewModel> (Label.TextProperty, vm => vm.Name, mode: BindingMode.OneWayToSource);

viewmodel.Name = "John Doe";
Debug.WriteLine (label.Text); //prints ""
label.Text = "Foo";
Debug.WriteLine (viewmodel.Name); //prints "Foo"