diff --git a/Extenso.Core/Collections/EnumerableExtensions.cs b/Extenso.Core/Collections/EnumerableExtensions.cs
index be901bb..7877fdc 100644
--- a/Extenso.Core/Collections/EnumerableExtensions.cs
+++ b/Extenso.Core/Collections/EnumerableExtensions.cs
@@ -136,31 +136,25 @@ public static bool HasMoreThan<T>(this IEnumerable<T> source, int n)
                 //throw new ArgumentNullException("source");
             }
 
-            var array = source as T[];
-
-            if (array != null)
+            if (source is T[] array)
             {
                 return array.Length > n;
             }
 
-            var collection = source as ICollection<T>;
-
-            if (collection != null)
+            if (source is ICollection<T> collection)
             {
                 return collection.Count > n;
             }
 
-            using (var enumerator = source.GetEnumerator())
+            using var enumerator = source.GetEnumerator();
+            for (int i = 0; i < n + 1; i++)
             {
-                for (int i = 0; i < n + 1; i++)
+                if (!enumerator.MoveNext())
                 {
-                    if (!enumerator.MoveNext())
-                    {
-                        return false;
-                    };
-                }
-                return true;
+                    return false;
+                };
             }
+            return true;
         }
 
         /// <summary>
@@ -684,16 +678,12 @@ internal static bool FastAny<TSource>(this IEnumerable<TSource> source)
                 throw new ArgumentNullException(nameof(source));
             }
 
-            var array = source as TSource[];
-
-            if (array != null)
+            if (source is TSource[] array)
             {
                 return array.Length > 0;
             }
 
-            var collection = source as ICollection<TSource>;
-
-            if (collection != null)
+            if (source is ICollection<TSource> collection)
             {
                 return collection.Count > 0;
             }
diff --git a/Extenso.Core/ObjectExtensions.cs b/Extenso.Core/ObjectExtensions.cs
index 1cda7d2..89f5112 100644
--- a/Extenso.Core/ObjectExtensions.cs
+++ b/Extenso.Core/ObjectExtensions.cs
@@ -219,7 +219,7 @@ public static bool In<T>(this T source, params T[] values)
         /// <returns>true if source is equal to the default value of its type; otherwise false.</returns>
         public static bool IsDefault<T>(this T source)
         {
-            return source.GenericEquals(default(T));
+            return source.GenericEquals(default);
         }
 
         /// <summary>
diff --git a/Extenso.Core/StringExtensions.cs b/Extenso.Core/StringExtensions.cs
index 7ef4a5e..020ed77 100644
--- a/Extenso.Core/StringExtensions.cs
+++ b/Extenso.Core/StringExtensions.cs
@@ -24,7 +24,7 @@ public static class StringExtensions
         #region Fields
 
         private const string RegexArabicAndHebrew = @"[\u0600-\u06FF,\u0590-\u05FF]+";
-        private static readonly char[] validSegmentChars = "/?#[]@\"^{}|`<>\t\r\n\f ".ToCharArray();
+        //private static readonly char[] validSegmentChars = "/?#[]@\"^{}|`<>\t\r\n\f ".ToCharArray();
 
         #endregion Fields
 
@@ -96,9 +96,9 @@ public static T Base64Deserialize<T>(this string source)
             }
             else
             {
-                int length = int.Parse(source.Substring(0, lengthDelimiterPosition));
+                int length = int.Parse(source[..lengthDelimiterPosition]);
 
-                var bytes = Convert.FromBase64String(source.Substring(lengthDelimiterPosition + 1));
+                var bytes = Convert.FromBase64String(source[(lengthDelimiterPosition + 1)..]);
                 using (var memoryStream = new MemoryStream(bytes, 0, length))
                 {
                     var binaryFormatter = new BinaryFormatter();
@@ -129,7 +129,7 @@ public static string Between(this string source, char left, char right)
                 int indexTo = source.IndexOf(right, indexFrom);
                 if (indexTo != -1)
                 {
-                    return source.Substring(indexFrom, indexTo - indexFrom);
+                    return source[indexFrom..indexTo];
                 }
             }
             return string.Empty;
@@ -530,7 +530,7 @@ public static string Left(this string source, int length)
                 return source;
             }
 
-            return source.Substring(0, length);
+            return source[..length];
         }
 
         /// <summary>
@@ -549,7 +549,7 @@ public static string LeftOf(this string source, char value)
             int index = source.IndexOf(value);
             if (index != -1)
             {
-                return source.Substring(0, index);
+                return source[..index];
             }
             return source;
         }
@@ -578,7 +578,7 @@ public static string LeftOf(this string source, char value, int n)
             }
             if (index != -1)
             {
-                return source.Substring(0, index);
+                return source[..index];
             }
             return source;
         }
@@ -599,7 +599,7 @@ public static string LeftOf(this string source, string value)
             int index = source.IndexOf(value);
             if (index != -1)
             {
-                return source.Substring(0, index);
+                return source[..index];
             }
             return source;
         }
@@ -621,7 +621,7 @@ public static string LeftOfLastIndexOf(this string source, char value)
             int index = source.LastIndexOf(value);
             if (index != -1)
             {
-                ret = source.Substring(0, index);
+                ret = source[..index];
             }
             return ret;
         }
@@ -643,7 +643,7 @@ public static string LeftOfLastIndexOf(this string source, string value)
             int index = source.LastIndexOf(value);
             if (index != -1)
             {
-                ret = source.Substring(0, index);
+                ret = source[..index];
             }
             return ret;
         }
@@ -673,7 +673,7 @@ public static string Prepend(this string source, params string[] values)
         {
             var items = new string[values.Length + 1];
             values.CopyTo(items, 0);
-            items[items.Length - 1] = source;
+            items[^1] = source;
             return string.Concat(items);
         }
 
@@ -687,7 +687,7 @@ public static string Prepend(this string source, params object[] values)
         {
             var items = new object[values.Length + 1];
             values.CopyTo(items, 0);
-            items[items.Length - 1] = source;
+            items[^1] = source;
             return string.Concat(items);
         }
 
@@ -795,7 +795,7 @@ public static string RightOf(this string source, char value)
             int index = source.IndexOf(value);
             if (index != -1)
             {
-                return source.Substring(index + 1);
+                return source[(index + 1)..];
             }
             return source;
         }
@@ -825,7 +825,7 @@ public static string RightOf(this string source, char value, int n)
 
             if (index != -1)
             {
-                return source.Substring(index + 1);
+                return source[(index + 1)..];
             }
             return source;
         }
@@ -846,7 +846,7 @@ public static string RightOf(this string source, string value)
             int index = source.IndexOf(value);
             if (index != -1)
             {
-                return source.Substring(index + 1);
+                return source[(index + 1)..];
             }
             return source;
         }
@@ -868,7 +868,7 @@ public static string RightOfLastIndexOf(this string source, char value)
             int index = source.LastIndexOf(value);
             if (index != -1)
             {
-                ret = source.Substring(index + 1);
+                ret = source[(index + 1)..];
             }
             return ret;
         }
@@ -890,7 +890,7 @@ public static string RightOfLastIndexOf(this string source, string value)
             int index = source.LastIndexOf(value);
             if (index != -1)
             {
-                ret = source.Substring(index + 1);
+                ret = source[(index + 1)..];
             }
             return ret;
         }
@@ -968,7 +968,7 @@ public static bool StartsWithAny(this string source, params string[] values)
         public static string ToCamelCase(this string source)
         {
             string pascal = source.ToPascalCase();
-            return string.Concat(pascal[0].ToString().ToLower(), pascal.Substring(1));
+            return string.Concat(pascal[0].ToString().ToLower(), pascal[1..]);
         }
 
         /// <summary>
@@ -1124,7 +1124,7 @@ public static T XmlDeserialize<T>(this string source)
         {
             if (string.IsNullOrEmpty(source))
             {
-                return default(T);
+                return default;
             }
 
             var locker = new object();
diff --git a/Extenso.Sandbox/Program.cs b/Extenso.Sandbox/Program.cs
index 909ee60..d3fb937 100644
--- a/Extenso.Sandbox/Program.cs
+++ b/Extenso.Sandbox/Program.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Text.RegularExpressions;
 using Extenso.Collections;
 using Extenso.Data;
@@ -19,6 +20,13 @@ private static void Main(string[] args)
 
             //DataTableExtensions();
 
+            //string sample = "key:value";
+            //string key = sample.LeftOf(':');
+            //string value = sample.RightOf(':');
+
+            string desc = "the quick brown fox jumped over the lazy dog";
+            string result = desc.AsSpan()[..19].ToString();
+
             Console.ReadLine();
         }
         private static string SeparatorReplacement(string value, string separator, bool capitalizeFirstChar)