using System;
using System.Text.RegularExpressions;
public class Test
{
    public static void Main()
    {   
        string msg= @"this.label1.Text = ""Code Smart"";";
        var charSetOccurences = new Regex(@"\.Text\s*=\s*""([^""]+)""", RegexOptions.IgnoreCase);
        var charSetMatches = charSetOccurences.Matches(msg);
        foreach (Match match in charSetMatches)
        {
            string result = match.Groups[1].Value;
            Console.WriteLine(result);
        }
    }
}

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