我们可以通过设置TabControl的TabItem的样式来修改TabItem的大小。下面是一段示例代码,
<Window x:Class="WpfTabItemSize.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<Style TargetType="{x:Type TabItem}">
<Setter Property="Width" Value="150"/>
</Style>
</Window.Resources>
<Grid>
<TabControl>
<TabItem >
<TabItem.Header>
<StackPanel Orientation="Horizontal">
<TextBlock>概况</TextBlock>
</StackPanel>
</TabItem.Header>
</TabItem>
<TabItem >
<TabItem.Header>
<StackPanel Orientation="Horizontal">
<TextBlock>用电</TextBlock>
</StackPanel>
</TabItem.Header>
</TabItem>
<TabItem >
<TabItem.Header>
<StackPanel Orientation="Horizontal">
<TextBlock>用水</TextBlock>
</StackPanel>
</TabItem.Header>
</TabItem>
</TabControl>
</Grid>
</Window>

谢谢!
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