请教这段内容如何用正则 进行匹配
<form class="formclass" id="loginform" method="post" onsubmit="return loginform();">
<div style="padding-bottom:5px">Username</div>
<div style="padding-bottom:5px"><input type="text" name="username" style="width:180px"></div>
<div style="padding-bottom:5px">Password</div>
<div style="padding-bottom:5px"><input type="password" name="password" style="width:180px"></div>
<div style="padding-bottom:5px"><div style="padding:5px 0px"><a href="javascript:void(0);" onclick="captchareload2();"><img src="modules/captcha/captcha.php?r=login" id="captchaimglogin" border="0"></a></div>
<script>function captchareload2(){
$("#captchaimglogin").attr('src','modules/captcha/captcha.php?r=login&x=34&y=75&z=119&?newtime=' + (new Date()).getTime());
}</script></div>
<div style="padding-bottom:5px"><input type="text" name="captcha" id="captcha_login" style="width:180px"></div>
<div style="padding-bottom:5px"><input type="submit" name="login" value="Login" class="orange"></div>
</form>
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上面这段内容:
1、把 <div style="padding-bottom:5px"><div style="padding:5px 0px"><a href="javascript:void(0);" onclick="captchareload2();"><img src="modules/captcha/captcha.php?r=login" id="captchaimglogin" border="0"></a></div>
<script>function captchareload2(){
$("#captchaimglogin").attr('src','modules/captcha/captcha.php?r=login&x=34&y=75&z=119&?newtime=' + (new Date()).getTime());
}</script></div>,取出来,用正则匹配
2、匹配 在<form></form>里是否包含 第1点 的内容,有包含 输出真,没包含输出假
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我是在搞不懂了,请帮帮忙
------解决方案--------------------PHP code
$s=<<<html
<form class="formclass" id="loginform" method="post" onsubmit="return loginform();">
<div style="padding-bottom:5px">Username</div>
<div style="padding-bottom:5px"><input type="text" name="username" style="width:180px"></div>
<div style="padding-bottom:5px">Password</div>
<div style="padding-bottom:5px"><input type="password" name="password" style="width:180px"></div>
<div style="padding-bottom:5px"><div style="padding:5px 0px"><a href="javascript:void(0);" onclick="captchareload2();"><img src="modules/captcha/captcha.php?r=login" id="captchaimglogin" border="0"></a></div>
<script>function captchareload2(){
$("#captchaimglogin").attr('src','modules/captcha/captcha.php?r=login&x=34&y=75&z=119&?newtime=' + (new Date()).getTime());
}</script></div>
<div style="padding-bottom:5px"><input type="text" name="captcha&quo