如何使用 SelectSingleNode 获取OverallResult 元素的内部文本?
<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<soap:Body>
<ProcessResp xmlns="http://www.w3.org/2005/Atom">
<Result>
<OverallResult>Success</OverallResult>