需求
在使用WPF開發時，使用DataGrid列表顯示數據時，有些字段可以進行分組顯示，用於更好的表達它們之間存在的某種關系，因此就考慮到要對DataGrid的表頭進行擴展，可以顯示多行表頭，讓這些有關聯的字段內容顯示的更加明了簡潔。
自定義樣式
這段自定義樣式可以放在MainWindow.xaml文件中，或者自己定義一個存放樣式文件的xaml進行存放。
這里在模版里面使用的第一個Grid，是用於總的顯示，還有右側邊豎線分割線，嵌入的Grid用於顯示多表頭的處理顯示功能：第一行為總的信息，第二行為第一行和第三行的分割線，第三行顯示的省、市和縣。
<Style x:Key="CityStyle" TargetType="DataGridColumnHeader">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate>
<Grid x:Name="Root">
<Grid.ColumnDefinitions>
<ColumnDefinition>
</ColumnDefinition>
<ColumnDefinition Width="Auto">
</ColumnDefinition>
</Grid.ColumnDefinitions>
<Grid
Grid.Column="0"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<Grid.RowDefinitions>
<RowDefinition Height="30">
</RowDefinition>
<RowDefinition Height="Auto"></RowDefinition>
<RowDefinition Height="30">
</RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100">
</ColumnDefinition>
<ColumnDefinition Width="Auto">
</ColumnDefinition>
<ColumnDefinition Width="100">
</ColumnDefinition>
<ColumnDefinition Width="Auto">
</ColumnDefinition>
<ColumnDefinition Width="100">
</ColumnDefinition>
</Grid.ColumnDefinitions>
<ContentPresenter
Grid.Row="0"
Grid.Column="0"
Grid.ColumnSpan="5"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Content="戶籍信息">
</ContentPresenter>
<Rectangle
Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="5"
VerticalAlignment="Stretch" Height="1"
Fill="Black"
Visibility="Visible">
</Rectangle>
<ContentPresenter
Grid.Row="2"
Grid.Column="0"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Content="省">
</ContentPresenter>
<Rectangle
Grid.Row="2"
Grid.Column="1"
Width="1"
VerticalAlignment="Stretch"
Fill="#ccc"
Visibility="Visible">
</Rectangle>
<ContentPresenter
Grid.Row="2"
Grid.Column="2"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Content="市">
</ContentPresenter>
<Rectangle
Grid.Row="2"
Grid.Column="3"
Width="1"
VerticalAlignment="Stretch"
Fill="#ccc"
Visibility="Visible">
</Rectangle>
<ContentPresenter
Grid.Row="2"
Grid.Column="4"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Content="縣">
</ContentPresenter>
</Grid>
<Rectangle
Grid.Column="1"
Width="1"
VerticalAlignment="Stretch"
Fill="#ccc"
Visibility="Visible">
</Rectangle>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
窗體布局
<Grid>
<DataGrid
AutoGenerateColumns="False"
CanUserAddRows="False"
ItemsSource="{Binding UserInformations}">
<DataGrid.Columns>
<DataGridTextColumn Width="100" Binding="{Binding UserName}">
<DataGridTextColumn.HeaderTemplate>
<DataTemplate>
<Grid HorizontalAlignment="Stretch" VerticalAlignment="Center">
<TextBlock
Margin="5,0,5,0"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="姓名"
TextAlignment="Center"
TextWrapping="Wrap">
</TextBlock>
</Grid>
</DataTemplate>
</DataGridTextColumn.HeaderTemplate>
<DataGridTextColumn.ElementStyle>
<Style>
<Setter Property="TextBlock.TextAlignment" Value="Center">
</Setter>
<Setter Property="TextBlock.TextWrapping" Value="Wrap">
</Setter>
<Setter Property="TextBlock.HorizontalAlignment" Value="Center">
</Setter>
<Setter Property="TextBlock.VerticalAlignment" Value="Center">
</Setter>
</Style>
</DataGridTextColumn.ElementStyle>
</DataGridTextColumn>
<DataGridTemplateColumn HeaderStyle="{StaticResource CityStyle}">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock
Width="100"
Margin="0"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="{Binding Province}"
TextAlignment="Center">
</TextBlock>
<Rectangle Width="1" Fill="Black">
</Rectangle>
<TextBlock
Width="100"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="{Binding City}"
TextAlignment="Center">
</TextBlock>
<Rectangle Width="1" Fill="Black">
</Rectangle>
<TextBlock
Width="100"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="{Binding County}"
TextAlignment="Center">
</TextBlock>
</StackPanel>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
<DataGridTextColumn
Width="100"
Binding="{Binding Motto}"
Header="格言">
<DataGridTextColumn.HeaderStyle>
<Style>
<Setter Property="TextBlock.HorizontalAlignment" Value="Stretch">
</Setter>
<Setter Property="TextBlock.TextAlignment" Value="Center">
</Setter>
</Style>
</DataGridTextColumn.HeaderStyle>
<DataGridTextColumn.HeaderTemplate>
<DataTemplate>
<TextBlock
HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="格言"
TextAlignment="Center"
TextWrapping="Wrap">
</TextBlock>
</DataTemplate>
</DataGridTextColumn.HeaderTemplate>
<DataGridTextColumn.ElementStyle>
<Style>
<Setter Property="TextBlock.TextAlignment" Value="Center">
</Setter>
<Setter Property="TextBlock.TextWrapping" Value="Wrap">
</Setter>
<Setter Property="TextBlock.HorizontalAlignment" Value="Center">
</Setter>
<Setter Property="TextBlock.VerticalAlignment" Value="Center">
</Setter>
</Style>
</DataGridTextColumn.ElementStyle>
</DataGridTextColumn>
</DataGrid.Columns>
</DataGrid>
</Grid>
在這里的窗體布局中，同時對姓名和格言的表頭樣式和Cell里面的樣式進行了修改。其中DataGridTextColumn.HeaderTemplate包括的是頭部的樣式；DataGridTextColumn.ElementStyle寶開的是Cell的樣式。
定義的實體類
public class UserInformation
{
public string UserName { get; set; }
public string Province { get; set; }
public string City { get; set; }
public string County { get; set; }
public int Age { get; set; }
public string Motto { get; set; }
}
ViewModel類的定義
public class MainViewModel:ViewModelBase
{
private string _title;
public string Title
{
get { return _title; }
set { Set(ref _title, value); }
}
private ObservableCollection<UserInformation> _userInformations;
public ObservableCollection<UserInformation> UserInformations
{
get { return _userInformations; }
set { Set(ref _userInformations, value); }
}
public MainViewModel()
{
Title = Guid.NewGuid().ToString();
UserInformations = new ObservableCollection<UserInformation>(new List<UserInformation>()
{
new UserInformation()
{
UserName = "Bob",Age = 32,Province = "山東",City = "濟南",County = "天橋",Motto = "會當雲絕頂，\r\n一覽眾山小。"
},
new UserInformation()
{
UserName = "Bob",Age = 32,Province = "山東",City = "濟南",County = "天橋",Motto = "會當雲絕頂，\r\n一覽眾山小。"
},
new UserInformation()
{
UserName = "Bob",Age = 32,Province = "山東",City = "濟南",County = "天橋",Motto = "會當雲絕頂，\r\n一覽眾山小。"
}
});
}
}
本實例使用了.netcore 3.1版本進行的開發，但是對於.net framework同樣適用。
MVVM模式是使用MVVMLightstd10，可以從nuget上面進行下載。
本示例已上傳至GITHUB：https://github.com/mzy666888/MultiHeaderOfDataGridWpfApp