关于VC BOOST 正则表达式的问题

<td class="td1">2013-12-31</td>
<td class="td2">
<a href="/lottery/draw/view/52?phase=2013001">2013001</a>
</td>
<td class="td3"><span class="result"> <span class="ball_1">9</span>
<span class="ball_1">6</span>
<span class="ball_1">8</span>



上面的代码截取自网页

根据这段代码，自己整理出了段正则表达式，在工具中测试OK

正则如下：“<td\s*class="td1">\d{4}-\d{2}-\d{2}</td>\s*<td\s*class="td2">\s*<a\s*href="/lottery/draw/view/52.phase=\d+">\d+</a>\s*</td>\s*<td \s*class="td3"><span\s*class="result">\s*<span\s*class="ball_1">\d+</span>\s*<span\s+class="ball_1">\d+</span>\s*<span\s*class="ball_1">\d+</span>”



strHtml变量是个cstring类型，存储了打开的网页源码，我现在想知道的是，为什么我通关下面的按钮事件，不能正则到我想要的东西？

boost::tregex expression(_(T"上面的正则代码");
CString sRet;
CString in = _T("");
boost::tmatch what;
if(boost::regex_match(strHtml, what, expression))//CString转string
{
for(int i=0;i<what.size();i++)
{
sRet = CString(what[i].first, what.length(i));
MessageBox(sRet);
}
}
else
{
MessageBox(_T("Error Input"));
}