using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?!<[^>]*?>)\bhello world\b(?![^<]*?(?:</[^/]*>|>))";
string input = @"one two three hello world four five
one <a href='index.html'> hello world </a> four five
foo bar <p>hello world</p> hello
<p name=""hello world"">hello world</p>
one two three <img alt='hello world' \>four five
<img alt=""hello world""> foo
foo bar <a href=""index.html"">hello world</a> again
one two three hello world four five
one two three <img alt='hello world' \>four five";
foreach (Match m in Regex.Matches(input, pattern))
{
Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index);
}
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx