尝试学习如何将对象绑定(bind)到各种类型的控件。在这种情况下,我想让我的对象中的示例数据出现在 ComboBox 中。代码运行,但出现的不是值(大卫、海伦、乔)是文本“TheProtect.UserControls.Client”)
XAML:(ucDataBindingObject.xaml)
<UserControl x:Class="TheProject.UserControls.ucDataBindingObject"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
Width="Auto"
Height="Auto"
mc:Ignorable="d">
<Grid Width="130"
Height="240"
Margin="0">
<ComboBox Width="310"
HorizontalAlignment="Left"
VerticalAlignment="Top"
ItemsSource="{Binding Path=Clients}" />
</Grid>
</UserControl>
C#:ucDataBindingObject.xaml.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Controls;
namespace TheProject.UserControls
{
public partial class ucDataBindingObject : UserControl
{
public List<Client> Clients { get; set; }
public ucDataBindingObject()
{
Clients = new List<Client>();
Clients.Add(new Client(1, "David")); // sample data
Clients.Add(new Client(2, "Helen"));
Clients.Add(new Client(3, "Joe"));
InitializeComponent();
this.DataContext = this;
}
}
C# 客户端.cs
using System;
using System.Linq;
namespace TheProject.UserControls
{
public class Client
{
public int ID { get; set; }
public string Name { get; set; }
public Client(int id, string name)
{
this.ID = id;
this.Name = name;
}
}
}
最佳答案
有几种方法可以告诉框架要显示什么
1) 使用 DisplayMemberPath
在 ComboBox 上(这将显示命名属性):
<ComboBox ItemsSource="{Binding Path=Clients}"
DisplayMemberPath="Name"
/>
2) 设置
ItemTemplate
在组合框上。这就像#1,除了允许您定义要显示的模板,而不仅仅是一个属性:<ComboBox ItemsSource="{Binding Path=Clients}">
<ComboBox.ItemTemplate>
<DataTemplate>
<Border BorderBrush="Green" BorderThickness="1" Padding="5">
<TextBlock Text="{Binding Path=Name,StringFormat='Name: {0}'}" />
</Border>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
3) 添加
ToString()
覆盖到源类。如果您总是想为给定的类显示相同的字符串,这很有用。 (请注意,默认 ToString()
只是类类型名称,这就是您看到“TheProtect.UserControls.Client”的原因。)public class Client
{
// ...
public override string ToString()
{
return string.Format("{0} ({1})", Name, ID);
}
}
4) 添加
DataTemplate
到 XAML 资源。这对于将给定的类类型与更复杂或风格化的模板相关联很有用。<UserControl xmlns:local="clr-namespace:TheProject.UserControls">
<UserControl.Resources>
<DataTemplate DataType="local:Client">
<TextBlock Text="{Binding Name}" />
</DataTemplate>
</UserControl.Resources>
// ...
</UserControl>
关于WPF:如何将对象绑定(bind)到组合框,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/19071664/