wordpress建站过程中，很多时候，我们的文章中没有设置特色图片，但是我们想显示出来这篇文章中的第一张图片，下面介绍一下方法：
1. 切换到你主题所在目录，打开function.PHP文件，加入下面这段代码：
注：此方法工作原理是查找文章内有没img这个标签，如果有就调出第一张图片，如果没有就用一张设计好的图片代替
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Crayon-button Crayon-expand-button" title="Expand Code">
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Crayon-button Crayon-copy-button" title="Copy">
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Crayon-button Crayon-popup-button" title="Open Code In New Window">
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