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<p>Web前端</p>
<ul style="display:block">
<li>JavaScript</li>
<li>DIV+CSS</li>
<li>jQuery</li>
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<p>后台脚本</p>
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<li>PHP</li>
<li>ASP.net</li>
<li>JSP</li>
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<p>前端框架</p>
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<li>Extjs</li>
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<li>YUI</li>
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![实现计算器功能[图]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)