新的WPF数据绑定 [英] New to WPF Data Binding

问题描述

我新的WPF数据绑定，有点卡住了。结果
显然我的文本框不正确绑定到数据元素我打算，我想不通为什么。

I'm new to WPF Data binding, and a bit stuck.
Apparently my textbox is not correctly bound to the data element I intend, and I cannot figure out why.

首先在我的 MainWindow.xaml 文件，我宣布一个对象：

First in my MainWindow.xaml file, I declare an object:

<Window.Resources>
    <local:Aircraft x:Key="Aircraft"/>
</Window.Resources>

这期间 MainWindow.InitializeComponent（）结果


This creates an object of type Aircraft during MainWindow.InitializeComponent()
(I can verify this by putting a breakpoint on the constructor of Aircraft)

类飞机（我可以把飞机上的构造函数断点验证） 在的.cs 文件中定义，财产试验拥有财产重量，使 myAircraft.Pilot.Weight 是 INT 。

Class Aircraft is defined in a .cs file, with property Pilot which has property Weight, so that myAircraft.Pilot.Weight is an int.

接下来，我尝试绑定一个文本框此属性：

Next, I try to bind a textbox to this property:

<TextBox Name="PICWeight" DataContext="{Binding Source={StaticResource Aircraft}, Path=Pilot.Weight}" />

应用程序编译和运行，但是当我把数字文本到文本框中，然后将焦点移到另一个文本框，我希望看到的二传手为 Pilot.Weight 被调用（我有它一个断点）。事实并非如此。

The application compiles and runs, but when I put numeric text into the textbox, then move the focus to another textbox, I expect to see the setter for Pilot.Weight get called (I have a breakpoint on it). It doesn't.

我认为，应该从字符串默认ValueConverter（从文本框）为int（Weight属性的类型），以及文本框应该有引发LostFocus 的默认的更新源事件。

I believe that there should be a default ValueConverter from String (from the textbox) to int (the type of the Weight property), and that textboxes should have default update-source event of LostFocus.

我是指定绑定是否正确？结果
我需要创建一个ValueConverter，或明确指定更新事件？结果
还有什么我做错了？

Am I specifying the binding properly?
Do I need to create a ValueConverter, or explicitly specify the update event?
Is there anything else I'm doing wrong?

推荐答案

您需要将文本属性绑定，而不仅仅是DataContext的，如：

You need to bind the Text property, not just DataContext, like:

<TextBox Name="PICWeight" DataContext="{Binding Source={StaticResource Aircraft}}" Text="{Binding Path=Pilot.Weight}" />

或

<TextBox Name="PICWeight" Text="{Binding Source={StaticResource Aircraft}, Path=Pilot.Weight}" />

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