using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?(DEFINE)
(?<expr> \w+ | '[\w\s]*' | ""[\s\w]*"" | \(\s*(?&expr)\s*\) )
(?<clause> (?&expr)\s*=\s*(?&expr) )
(?<case> case \s+ when \s+ (?&clause) \s+ then \s+ (?&expr) \s+ else \s+ (?&expr) \s+ end)
)
(?i)(\s* (?&case) \s*)+";
string input = @"iduser + CaSe WhEn (""end"") = 0 THEN 'CASE WHEN' ELSE ' END ' END + sum(iduser ) + CASE WHEN LANGUAGE = 3 THEN 4 ELSE 5 END";
RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnorePatternWhitespace | RegexOptions.IgnoreCase;
foreach (Match m in Regex.Matches(input, pattern, options))
{
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