用VS新建WinForm程序，窗体上是三个文本框和一个按钮。
可以自己构造正则表达式，自己修改匹配内容
正则表达是要提取的部分为hewenqitext
代码如下：
using System;
using System.Text.RegularExpressions;
using System.Windows.Forms; namespace HoverTreeBatch.HoverTree
{
public partial class RegexForm : Form
{
public RegexForm()
{
InitializeComponent();
textBox_regex.Text = @"<img\b[^<>]*?\bsrc[\s\t\r\n]*=[\s\t\r\n]*[""']?[\s\t\r\n]*(?<hewenqitext>[^\s\t\r\n""'<>]*)[^<>]*?/?[\s\t\r\n]*>";
textBox_content.Text = @"<div class=""dengxaing-hovertree-com""><a title=""何问起批量2"" href=""http://hovertree.com/hvtimg/201601/p3t2ldyr.png""><img src=""http://hovertree.com/hvtimg/201601/p3t2ldyr_l.png"" style=""width:180px;height:140px;"" /></a><a title=""VS2015开发人员命令提示查看PublicKeyToken(公钥标记)"" href=""http://hovertree.com/hvtimg/201601/wn0bamxp.png""><img src=""http://hovertree.com/hvtimg/201601/wn0bamxp_l.png"" style=""width:180px;height:140px;"" /></a><a title=""消灭僵尸游戏"" href=""http://hovertree.com/hvtimg/201601/q47add2k.jpg""><img src=""http://hovertree.com/hvtimg/201601/q47add2k_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""纯CSS3漂亮的房子不错的天气"" href=""http://hovertree.com/hvtimg/201601/lbau8hqb.png""><img src=""http://hovertree.com/hvtimg/201601/lbau8hqb_l.png"" style=""width:180px;height:140px;"" /></a><a title=""HoverClock"" href=""http://hovertree.com/hvtimg/201601/thbniyjx.png""><img src=""http://hovertree.com/hvtimg/201601/thbniyjx_l.png"" style=""width:180px;height:140px;"" /></a><a title=""javascript元旦倒计时特效"" href=""http://hovertree.com/hvtimg/201512/o9qashmi.gif""><img src=""http://hovertree.com/hvtimg/201512/o9qashmi_l.gif"" style=""width:180px;height:140px;"" /></a><a title=""下雨"" href=""http://hovertree.com/hvtimg/201512/f748s0ko.jpg""><img src=""http://hovertree.com/hvtimg/201512/f748s0ko_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""何问起直接说喜欢你！"" href=""http://hovertree.com/hvtimg/201512/vt1tf0xl.jpg""><img src=""http://hovertree.com/hvtimg/201512/vt1tf0xl_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""IIS7，IIS7.5 URL重写模块工具"" href=""http://hovertree.com/hvtimg/201512/ew4yb78b.png""><img src=""http://hovertree.com/hvtimg/201512/ew4yb78b_l.png"" style=""width:180px;height:140px;"" /></a><a title=""山水画"" href=""http://hovertree.com/hvtimg/201512/agagq0or.jpg""><img src=""http://hovertree.com/hvtimg/201512/agagq0or_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""刘德华"" href=""http://hovertree.com/hvtimg/201512/r51a22uy.gif""><img src=""http://hovertree.com/hvtimg/201512/r51a22uy_l.gif"" style=""width:180px;height:140px;"" /></a><a title=""IIS为网站设置域名"" href=""http://hovertree.com/hvtimg/201512/69yoeuhf.jpg""><img src=""http://hovertree.com/hvtimg/201512/69yoeuhf_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""HoverTreeCMS分成"" href=""http://hovertree.com/hvtimg/201512/jgi94fdf.png""><img src=""http://hovertree.com/hvtimg/201512/jgi94fdf_l.png"" style=""width:180px;height:140px;"" /></a><a title=""范冰冰"" href=""http://hovertree.com/hvtimg/201511/6j9j6tk5.png""><img src=""http://hovertree.com/hvtimg/201511/6j9j6tk5_l.png"" style=""width:180px;height:140px;"" /></a><a title=""周末愉快"" href=""http://hovertree.com/hvtimg/201511/60mj4wsb.gif""><img src=""http://hovertree.com/hvtimg/201511/60mj4wsb_l.gif"" style=""width:180px;height:140px;"" /></a><a title=""谢霆锋手机背景图"" href=""http://hovertree.com/hvtimg/201508/cnvkv745.jpg""><img src=""http://hovertree.com/hvtimg/201508/cnvkv745_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""现代舞舞蹈家玛莎·葛兰姆动画Logo"" href=""http://hovertree.com/hvtimg/201506/ufigfjvn.jpg""><img src=""http://hovertree.com/hvtimg/201506/ufigfjvn_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""每次吵架，都希望男票这样解决战斗。。。"" href=""http://hovertree.com/hvtimg/201506/iqoqrhfn.gif""><img src=""http://hovertree.com/hvtimg/201506/iqoqrhfn_l.gif"" style=""width:180px;height:140px;"" /></a><a title=""现代舞舞蹈家玛莎·葛兰姆动画Logo"" href=""http://hovertree.com/hvtimg/201506/xlyxp4wg.png""><img src=""http://hovertree.com/hvtimg/201506/xlyxp4wg_l.png"" style=""width:180px;height:140px;"" /></a><a title=""美女"" href=""http://hovertree.com/hvtimg/201506/m921jw4n.jpg""><img src=""http://hovertree.com/hvtimg/201506/m921jw4n_l.jpg"" style=""width:180px;height:140px;"" /></a></div>";
} private void button_ok_Click(object sender, EventArgs e)
{
Regex m_hvtRegImg = new Regex(textBox_regex.Text, RegexOptions.IgnoreCase); //搜索匹配的字符串
MatchCollection hewenqi_matches;
try
{
hewenqi_matches = m_hvtRegImg.Matches(textBox_content.Text); // 取得匹配项列表
foreach (Match match in hewenqi_matches)
{
textBox_result.Text = textBox_result.Text + match.Groups["hewenqitext"].Value + "\r\n";
}
}
catch (Exception ex)
{
textBox_result.Text = ex.ToString();
} }
}
} /*
<div class="dengxaing-hovertree-com"> <a title="何问起批量2" href=""http://hovertree.com/hvtimg/201601/p3t2ldyr.png"">
<img src=""http://hovertree.com/hvtimg/201601/p3t2ldyr_l.png"" style="width:180px;height:140px;" /></a> <a title="VS2015开发人员命令提示查看PublicKeyToken(公钥标记)" href=""http://hovertree.com/hvtimg/201601/wn0bamxp.png"">
<img src=""http://hovertree.com/hvtimg/201601/wn0bamxp_l.png"" style="width:180px;height:140px;" /></a> <a title="消灭僵尸游戏" href=""http://hovertree.com/hvtimg/201601/q47add2k.jpg"">
<img src=""http://hovertree.com/hvtimg/201601/q47add2k_l.jpg"" style="width:180px;height:140px;" /></a> <a title="纯CSS3漂亮的房子不错的天气" href=""http://hovertree.com/hvtimg/201601/lbau8hqb.png"">
<img src=""http://hovertree.com/hvtimg/201601/lbau8hqb_l.png"" style="width:180px;height:140px;" /></a> <a title="HoverClock" href=""http://hovertree.com/hvtimg/201601/thbniyjx.png"">
<img src=""http://hovertree.com/hvtimg/201601/thbniyjx_l.png"" style="width:180px;height:140px;" /></a> <a title="javascript元旦倒计时特效" href=""http://hovertree.com/hvtimg/201512/o9qashmi.gif">
<img src=""http://hovertree.com/hvtimg/201512/o9qashmi_l.gif" style="width:180px;height:140px;" /></a> <a title="下雨" href=""http://hovertree.com/hvtimg/201512/f748s0ko.jpg"">
<img src=""http://hovertree.com/hvtimg/201512/f748s0ko_l.jpg"" style="width:180px;height:140px;" /></a> <a title="何问起直接说喜欢你！" href=""http://hovertree.com/hvtimg/201512/vt1tf0xl.jpg"">
<img src=""http://hovertree.com/hvtimg/201512/vt1tf0xl_l.jpg"" style="width:180px;height:140px;" /></a> <a title="IIS7，IIS7.5 URL重写模块工具" href=""http://hovertree.com/hvtimg/201512/ew4yb78b.png"">
<img src=""http://hovertree.com/hvtimg/201512/ew4yb78b_l.png"" style="width:180px;height:140px;" /></a> <a title="山水画" href=""http://hovertree.com/hvtimg/201512/agagq0or.jpg"">
<img src=""http://hovertree.com/hvtimg/201512/agagq0or_l.jpg"" style="width:180px;height:140px;" /></a> <a title="刘德华" href=""http://hovertree.com/hvtimg/201512/r51a22uy.gif">
<img src=""http://hovertree.com/hvtimg/201512/r51a22uy_l.gif" style="width:180px;height:140px;" /></a> <a title="IIS为网站设置域名" href=""http://hovertree.com/hvtimg/201512/69yoeuhf.jpg"">
<img src=""http://hovertree.com/hvtimg/201512/69yoeuhf_l.jpg"" style="width:180px;height:140px;" /></a> <a title="HoverTreeCMS分成" href=""http://hovertree.com/hvtimg/201512/jgi94fdf.png"">
<img src=""http://hovertree.com/hvtimg/201512/jgi94fdf_l.png"" style="width:180px;height:140px;" /></a> <a title="范冰冰" href=""http://hovertree.com/hvtimg/201511/6j9j6tk5.png"">
<img src=""http://hovertree.com/hvtimg/201511/6j9j6tk5_l.png"" style="width:180px;height:140px;" /></a> <a title="周末愉快" href=""http://hovertree.com/hvtimg/201511/60mj4wsb.gif">
<img src=""http://hovertree.com/hvtimg/201511/60mj4wsb_l.gif" style="width:180px;height:140px;" /></a> <a title="谢霆锋手机背景图" href=""http://hovertree.com/hvtimg/201508/cnvkv745.jpg"">
<img src=""http://hovertree.com/hvtimg/201508/cnvkv745_l.jpg"" style="width:180px;height:140px;" /></a> <a title="现代舞舞蹈家玛莎·葛兰姆动画Logo" href=""http://hovertree.com/hvtimg/201506/ufigfjvn.jpg"">
<img src=""http://hovertree.com/hvtimg/201506/ufigfjvn_l.jpg"" style="width:180px;height:140px;" /></a> <a title="每次吵架，都希望男票这样解决战斗。。。" href=""http://hovertree.com/hvtimg/201506/iqoqrhfn.gif">
<img src=""http://hovertree.com/hvtimg/201506/iqoqrhfn_l.gif" style="width:180px;height:140px;" /></a> <a title="现代舞舞蹈家玛莎·葛兰姆动画Logo" href=""http://hovertree.com/hvtimg/201506/xlyxp4wg.png"">
<img src=""http://hovertree.com/hvtimg/201506/xlyxp4wg_l.png"" style="width:180px;height:140px;" /></a> <a title="美女" href=""http://hovertree.com/hvtimg/201506/m921jw4n.jpg"">
<img src=""http://hovertree.com/hvtimg/201506/m921jw4n_l.jpg"" style="width:180px;height:140px;" /></a>
</div>
*/