WinForm Sample Method for Extracting Content Using Regular Expressions

In this paper, an example is given to illustrate the method of extracting content by using regular expressions in WinForm. Share it for your reference, as follows:

Create a new WinForm program with VS. There are 3 text boxes and 1 button on the form.

You can construct your own regular expressions and modify your own matches

Regular expression is the part to be extracted for hewenqitext

The code is as follows:

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="" Batch 2"" href=""http://localhost/hvtimg/201601/p3t2ldyr.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201601/p3t2ldyr_l.png"" style=""width:180px;height:140px;"" /></a><a title=""VS2015 Developer command prompt view PublicKeyToken( Public key token )"" href=""http://localhost/hvtimg/201601/wn0bamxp.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201601/wn0bamxp_l.png"" style=""width:180px;height:140px;"" /></a><a title="" Zombie elimination game "" href=""http://localhost/hvtimg/201601/q47add2k.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201601/q47add2k_l.jpg"" style=""width:180px;height:140px;"" /></a><a title="" Pure CSS3 Nice house, nice weather "" href=""http://localhost/hvtimg/201601/lbau8hqb.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201601/lbau8hqb_l.png"" style=""width:180px;height:140px;"" /></a><a title=""HoverClock"" href=""http://localhost/hvtimg/201601/thbniyjx.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201601/thbniyjx_l.png"" style=""width:180px;height:140px;"" /></a><a title=""javascript New Year's Day countdown special effects "" href=""http://localhost/hvtimg/201512/o9qashmi.gif" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/o9qashmi_l.gif"" style=""width:180px;height:140px;"" /></a><a title="" Rain "" href=""http://localhost/hvtimg/201512/f748s0ko.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/f748s0ko_l.jpg"" style=""width:180px;height:140px;"" /></a><a title="" Just say I like you! "" href=""http://localhost/hvtimg/201512/vt1tf0xl.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/vt1tf0xl_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""IIS7 , IIS7.5 URL Rewrite module tool "" href=""http://localhost/hvtimg/201512/ew4yb78b.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/ew4yb78b_l.png"" style=""width:180px;height:140px;"" /></a><a title="" Landscape painting "" href=""http://localhost/hvtimg/201512/agagq0or.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/agagq0or_l.jpg"" style=""width:180px;height:140px;"" /></a><a title="" Andy Lau "" href=""http://localhost/hvtimg/201512/r51a22uy.gif" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/r51a22uy_l.gif"" style=""width:180px;height:140px;"" /></a><a title=""IIS Set the domain name for the site "" href=""http://localhost/hvtimg/201512/69yoeuhf.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/69yoeuhf_l.jpg"" style=""width:180px;height:140px;"" /></a><a title=""HoverTreeCMS Divided into "" href=""http://localhost/hvtimg/201512/jgi94fdf.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201512/jgi94fdf_l.png"" style=""width:180px;height:140px;"" /></a><a title="" Fan Bingbing "" href=""http://localhost/hvtimg/201511/6j9j6tk5.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201511/6j9j6tk5_l.png"" style=""width:180px;height:140px;"" /></a><a title="" Have a nice weekend "" href=""http://localhost/hvtimg/201511/60mj4wsb.gif" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201511/60mj4wsb_l.gif"" style=""width:180px;height:140px;"" /></a><a title="" Nicholas Tse mobile phone background map "" href=""http://localhost/hvtimg/201508/cnvkv745.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201508/cnvkv745_l.jpg"" style=""width:180px;height:140px;"" /></a><a title="" Modern dance dancer Martha Graham animation Logo"" href=""http://localhost/hvtimg/201506/ufigfjvn.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201506/ufigfjvn_l.jpg"" style=""width:180px;height:140px;"" /></a><a title="" Every time I quarrel, I hope that the men's tickets will solve the battle like this. . . "" href=""http://localhost/hvtimg/201506/iqoqrhfn.gif" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201506/iqoqrhfn_l.gif"" style=""width:180px;height:140px;"" /></a><a title="" Modern dance dancer Martha Graham animation Logo"" href=""http://localhost/hvtimg/201506/xlyxp4wg.png" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/hvtimg/201506/xlyxp4wg_l.png"" style=""width:180px;height:140px;"" /></a><a title="" Beauty "" href=""http://localhost/hvtimg/201506/m921jw4n.jpg" rel="external nofollow" rel="external nofollow" "><img src=""http://localhost/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);
// Search for matching strings 
MatchCollection hewenqi_matches;
try
{
hewenqi_matches = m_hvtRegImg.Matches(textBox_content.Text);
//  Get a list of matches 
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=" Batch 2" href=""http://localhost/hvtimg/201601/p3t2ldyr.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201601/p3t2ldyr_l.png"" style="width:180px;height:140px;" /></a>
<a title="VS2015 Developer command prompt view PublicKeyToken( Public key token )" href=""http://localhost/hvtimg/201601/wn0bamxp.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201601/wn0bamxp_l.png"" style="width:180px;height:140px;" /></a>
<a title=" Zombie elimination game " href=""http://localhost/hvtimg/201601/q47add2k.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201601/q47add2k_l.jpg"" style="width:180px;height:140px;" /></a>
<a title=" Pure CSS3 Nice house, nice weather " href=""http://localhost/hvtimg/201601/lbau8hqb.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201601/lbau8hqb_l.png"" style="width:180px;height:140px;" /></a>
<a title="HoverClock" href=""http://localhost/hvtimg/201601/thbniyjx.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201601/thbniyjx_l.png"" style="width:180px;height:140px;" /></a>
<a title="javascript New Year's Day countdown special effects " href=""http://localhost/hvtimg/201512/o9qashmi.gif" rel="external nofollow" rel="external nofollow" >
<img src=""http://localhost/hvtimg/201512/o9qashmi_l.gif" style="width:180px;height:140px;" /></a>
<a title=" Rain " href=""http://localhost/hvtimg/201512/f748s0ko.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201512/f748s0ko_l.jpg"" style="width:180px;height:140px;" /></a>
<a title=" Just say I like you! " href=""http://localhost/hvtimg/201512/vt1tf0xl.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201512/vt1tf0xl_l.jpg"" style="width:180px;height:140px;" /></a>
<a title="IIS7 , IIS7.5 URL Rewrite module tool " href=""http://localhost/hvtimg/201512/ew4yb78b.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201512/ew4yb78b_l.png"" style="width:180px;height:140px;" /></a>
<a title=" Landscape painting " href=""http://localhost/hvtimg/201512/agagq0or.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201512/agagq0or_l.jpg"" style="width:180px;height:140px;" /></a>
<a title=" Andy Lau " href=""http://localhost/hvtimg/201512/r51a22uy.gif" rel="external nofollow" rel="external nofollow" >
<img src=""http://localhost/hvtimg/201512/r51a22uy_l.gif" style="width:180px;height:140px;" /></a>
<a title="IIS Set the domain name for the site " href=""http://localhost/hvtimg/201512/69yoeuhf.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201512/69yoeuhf_l.jpg"" style="width:180px;height:140px;" /></a>
<a title="HoverTreeCMS Divided into " href=""http://localhost/hvtimg/201512/jgi94fdf.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201512/jgi94fdf_l.png"" style="width:180px;height:140px;" /></a>
<a title=" Fan Bingbing " href=""http://localhost/hvtimg/201511/6j9j6tk5.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201511/6j9j6tk5_l.png"" style="width:180px;height:140px;" /></a>
<a title=" Have a nice weekend " href=""http://localhost/hvtimg/201511/60mj4wsb.gif" rel="external nofollow" rel="external nofollow" >
<img src=""http://localhost/hvtimg/201511/60mj4wsb_l.gif" style="width:180px;height:140px;" /></a>
<a title=" Nicholas Tse mobile phone background map " href=""http://localhost/hvtimg/201508/cnvkv745.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201508/cnvkv745_l.jpg"" style="width:180px;height:140px;" /></a>
<a title=" Modern dance dancer Martha Graham animation Logo" href=""http://localhost/hvtimg/201506/ufigfjvn.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201506/ufigfjvn_l.jpg"" style="width:180px;height:140px;" /></a>
<a title=" Every time I quarrel, I hope that the men's tickets will solve the battle like this. . . " href=""http://localhost/hvtimg/201506/iqoqrhfn.gif" rel="external nofollow" rel="external nofollow" >
<img src=""http://localhost/hvtimg/201506/iqoqrhfn_l.gif" style="width:180px;height:140px;" /></a>
<a title=" Modern dance dancer Martha Graham animation Logo" href=""http://localhost/hvtimg/201506/xlyxp4wg.png" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201506/xlyxp4wg_l.png"" style="width:180px;height:140px;" /></a>
<a title=" Beauty " href=""http://localhost/hvtimg/201506/m921jw4n.jpg" rel="external nofollow" rel="external nofollow" ">
<img src=""http://localhost/hvtimg/201506/m921jw4n_l.jpg"" style="width:180px;height:140px;" /></a>
</div>
*/

PS: Here are two very convenient regular expression tools for your reference:

JavaScript Regular Expression Online Test Tool:
http://tools.ofstack.com/regex/javascript

Regular expression online generation tool:
http://tools.ofstack.com/regex/create_reg

For more readers interested in C # related content, please check the topics on this site: "WinForm Control Usage Summary", "C # Form Operation Skills Summary", "C # Data Structure and Algorithm Tutorial", "C # Common Control Usage Tutorial", "C # Object-Oriented Programming Introduction Tutorial" and "C # Programming Thread Use Skills Summary"

I hope this article is helpful to everyone's C # programming.