也许这能帮上忙:
<WrapPanel TextBlock.FontFamily="Verdana">
<Button Background="Blue">
<Viewbox>
<TextBlock Foreground="White">A</TextBlock>
</Viewbox>
</Button>
<Button Background="Blue">
<Viewbox>
<TextBlock Foreground="White">B</TextBlock>
</Viewbox>
</Button>
<Button Background="Blue">
<Viewbox>
<TextBlock Foreground="White">C</TextBlock>
</Viewbox>
</Button>
</WrapPanel>