“DataContext数据下上文”绑定不下， Why？

2012-08-28

“DataContext数据上下文”绑定不上， Why？？？“DataContext数据上下文”绑定不上， Why？？？思路：1、将“数据集类

“DataContext数据上下文”绑定不上， Why？？？
“DataContext数据上下文”绑定不上， Why？？？

思路：

1、将“数据集类的实例对象”赋值给“Grid”的数据上下文，DataContext。

2、“Grid”里有一个“Lable”，一个“DataGrid”进行数据绑定。

问题：数据绑定不上。

1、后台代码：

public partial class CustomReportTest : UserControl
{
public CustomReportTest()
{
InitializeComponent();

EnergyList energylist = new EnergyList();
LayoutRoot.DataContext = energylist;

//dg_EnergyCustom.ItemsSource = energylist.energylist;
}
}

public class EnergyList
{
private string _energytitle;

public string EnergyTitle
{
get {return _energytitle;}
set { _energytitle = "指标报表"; }
}

public List<EnergyTarget> energylist = new List<EnergyTarget> {
new EnergyTarget{EnergyYear="2010",EnergySum="7678.09",EnergyEveryOne="89.78",EnergyUnitArea="45.65"},
new EnergyTarget{EnergyYear="2011",EnergySum="8978.48",EnergyEveryOne="67.75",EnergyUnitArea="43.63"}
};
}

public class EnergyTarget
{

public string EnergyYear
{
get;
set;
}

public string EnergySum
{
get;
set;
}

public string EnergyUnitArea
{
get;
set;
}

public string EnergyEveryOne
{
get;
set;
}

}
2、XAML代码

<Grid x:Name="LayoutRoot" Background="White">
<Grid Margin="69,80,79,82">
<Grid.RowDefinitions>
<RowDefinition Height="30"/>
<RowDefinition/>
</Grid.RowDefinitions>

<sdk:Label Background="#FFB7D4E0" Content="{Binding EnergyTitle}"/>
<sdk:DataGrid Grid.Row="1" Name="dg_EnergyCustom" AutoGenerateColumns="False" ItemsSource="{Binding energylist}">
<sdk:DataGrid.Columns>
<sdk:DataGridTemplateColumn DisplayIndex="-1" Header="年份" IsReadOnly="True" Width="30*" >
<sdk:DataGridTemplateColumn.CellTemplate >
<DataTemplate>
<TextBlock FontSize="13" HorizontalAlignment="Center" VerticalAlignment="Center" Text="{Binding EnergyYear}"></TextBlock>
</DataTemplate>
</sdk:DataGridTemplateColumn.CellTemplate>
</sdk:DataGridTemplateColumn>
<sdk:DataGridTemplateColumn Header="项目" Width="30*">
<sdk:DataGridTemplateColumn.CellTemplate >
<DataTemplate>
<Grid ShowGridLines="True" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" >
<Grid.RowDefinitions>

<RowDefinition Height="20" />
<RowDefinition Height="20"/>
<RowDefinition Height="20"/>
</Grid.RowDefinitions>
<TextBlock Text="能耗量合计" Grid.Row="0" ></TextBlock>
<TextBlock Text="单位面积能耗" Grid.Row="1"></TextBlock>
<TextBlock Text="生均能耗" Grid.Row="2"></TextBlock>
</Grid>

</DataTemplate>
</sdk:DataGridTemplateColumn.CellTemplate>
</sdk:DataGridTemplateColumn>
<sdk:DataGridTemplateColumn Header="全校" Width="40*">
<sdk:DataGridTemplateColumn.CellTemplate >
<DataTemplate>
<Grid ShowGridLines="True" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<Grid.RowDefinitions>
<RowDefinition Height="20" />
<RowDefinition Height="20"/>
<RowDefinition Height="20"/>
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Text="{Binding EnergySum}" ></TextBlock>
<TextBlock Grid.Row="1" Text="{Binding EnergyUnitArea}" ></TextBlock>
<TextBlock Grid.Row="2" Text="{Binding EnergyEveryOne}"></TextBlock>
</Grid>

</DataTemplate>
</sdk:DataGridTemplateColumn.CellTemplate>
</sdk:DataGridTemplateColumn>
</sdk:DataGrid.Columns>

</sdk:DataGrid>

</Grid>
</Grid>

3、运行效果，数据绑定不上，Why???

[解决办法]
WPF?设断点瞅下。WPF还没玩过来。
[解决办法]
要绑定集合
LayoutRoot.DataContext = energylist.energylist;
[解决办法]

探讨

引用:

要绑定集合
LayoutRoot.DataContext = energylist.energylist;

页面初始化的时候已经绑定了啊。

如下：LayoutRoot.DataContext = energylist;

[解决办法]
EnergyList energylist = new EnergyList();
LayoutRoot.DataContext = energylist;
dg_EnergyCustom.ItemsSource = energylist.energylist;
要用dg_EnergyCustom绑定集合，将标记里的删掉，
没有意义，因为初始化时集合是空的，
只有实例化类后集合才有值，
这时绑定才不为空
亲测可行！

[解决办法]
你的energylist 必须要写属性。反则，界面获取不到数据。第一个字段也不对
[解决办法]
我给你改了一下。后台
public partial class MainWindow : Window

{
public MainWindow()
{
InitializeComponent();
EnergyList energylist = new EnergyList();
energylist.EnergyTitle = "指标报表";
LayoutRoot.DataContext = energylist;
}
}
public class EnergyList
{
private string _energytitle;

public string EnergyTitle
{
get { return _energytitle; }
set { _energytitle = "指标报表"; }
}

public EnergyList()
{
this.energylist= new List<EnergyTarget> {
new EnergyTarget{EnergyYear="2010",EnergySum="7678.09",EnergyEveryOne="89.78",EnergyUnitArea="45.65"},
new EnergyTarget{EnergyYear="2011",EnergySum="8978.48",EnergyEveryOne="67.75",EnergyUnitArea="43.63"}
};
}
private List<EnergyTarget> energylist = null;

public List<EnergyTarget> Energylist
{
get { return energylist; }
set { energylist = value; }
}
}

public class EnergyTarget
{

public string EnergyYear
{
get;
set;
}

public string EnergySum
{
get;
set;
}

public string EnergyUnitArea
{
get;
set;
}

public string EnergyEveryOne
{
get;
set;
}

}
前台
<Grid Name="LayoutRoot" >

<Grid.RowDefinitions>
<RowDefinition Height="30"/>
<RowDefinition/>
</Grid.RowDefinitions>

<Label Background="#FFB7D4E0" Content="{Binding EnergyTitle}"/>
<DataGrid Grid.Row="1" Name="dg_EnergyCustom" AutoGenerateColumns="False" ItemsSource="{Binding Energylist}">
<DataGrid.Columns>
<DataGridTemplateColumn Header="年份" IsReadOnly="True" Width="30*" >
<DataGridTemplateColumn.CellTemplate >
<DataTemplate>
<TextBlock FontSize="13" HorizontalAlignment="Center" VerticalAlignment="Center" Text="{Binding EnergyYear}"></TextBlock>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
<DataGridTemplateColumn Header="项目" Width="30*">
<DataGridTemplateColumn.CellTemplate >
<DataTemplate>
<Grid ShowGridLines="True" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" >
<Grid.RowDefinitions>
<RowDefinition Height="20" />
<RowDefinition Height="20"/>
<RowDefinition Height="20"/>
</Grid.RowDefinitions>
<TextBlock Text="能耗量合计" Grid.Row="0" ></TextBlock>
<TextBlock Text="单位面积能耗" Grid.Row="1"></TextBlock>
<TextBlock Text="生均能耗" Grid.Row="2"></TextBlock>

</Grid>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
<DataGridTemplateColumn Header="全校" Width="40*">
<DataGridTemplateColumn.CellTemplate >
<DataTemplate>
<Grid ShowGridLines="True" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<Grid.RowDefinitions>
<RowDefinition Height="20" />
<RowDefinition Height="20"/>
<RowDefinition Height="20"/>
</Grid.RowDefinitions>
<TextBlock Grid.Row="0" Text="{Binding EnergySum}" ></TextBlock>
<TextBlock Grid.Row="1" Text="{Binding EnergyUnitArea}" ></TextBlock>
<TextBlock Grid.Row="2" Text="{Binding EnergyEveryOne}"></TextBlock>
</Grid>

</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>

</DataGrid>
</Grid>
[解决办法]
问题1：
List没有继承INotifyCollectionChanged,所有集合发生变化的时候没法通知绑定的目标。
使用System.Collections.ObjectModel.ObservableCollection<T>

问题2：
随便baidu一下，C# 属性。
[解决办法]

探讨
引用:

问题1：
List没有继承INotifyCollectionChanged,所有集合发生变化的时候没法通知绑定的目标。
使用System.Collections.ObjectModel.ObservableCollection<T>

问题2：
随便baidu一下，C# 属性。

在客户端对属性进行“重新赋值”，然后绑定到客户端也要实现“Syste……

热点排行

C#

“DataContext数据下上文”绑定不下 ， Why？

“DataContext数据下上文”绑定不下， Why？