有了这个xml:
<div val1="q">a</div>
<div val2="w">b</div>
<div val3="e">c</div>
<div some="r">d</div>
<div thing="t">f</div>
<div name="y">g</div>
我们只想找到
<div val1="q">a</div>
<div val2="w">b</div>
<div val3="e">c</div>
哪些节点具有属性名称以其开头的属性val