方法很简单，将图片转换为<path>就可以了（需要用到Photoshop）
不过一般情况下制作按钮都不会用到这种方法，通常只要用image填充一张图片或者把路径转成按钮控件就可以了。
之所以这样做，是见到一位坛友提问说：如何根据PNG图片的形状来决定按钮的形状，，大概意思可能就是只有在PNG
图像形状范围内触发器才有效，不过他说的我也没怎么听明白，呵呵。。。自己试着做了一下。目前就想到了这个方法，也许还有更好的方法！
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WPF复杂形状按钮