├── .gitignore ├── L01.Ascii ├── L01.Ascii.csproj └── Program.cs ├── L02.EncodingAndUnicode ├── L02.EncodingAndUnicode.csproj └── Program.cs ├── L03.Instantiation ├── L03.Instantiation.csproj └── Program.cs ├── L04.L04.UnicodeAndStringComparison ├── L04.UnicodeAndStringComparison.csproj └── Program.cs ├── L05.InternPool ├── L05.InternPool.csproj └── Program.cs ├── L06.StringMethods ├── L06.StringMethods.csproj └── Program.cs └── Metigator44.sln /.gitignore: -------------------------------------------------------------------------------- 1 | ## Ignore Visual Studio temporary files, build results, and 2 | ## files generated by popular Visual Studio add-ons. 3 | ## 4 | ## Get latest from https://github.com/github/gitignore/blob/master/VisualStudio.gitignore 5 | 6 | # User-specific files 7 | *.rsuser 8 | *.suo 9 | *.user 10 | *.userosscache 11 | *.sln.docstates 12 | 13 | # User-specific files (MonoDevelop/Xamarin Studio) 14 | *.userprefs 15 | 16 | # Mono auto generated files 17 | mono_crash.* 18 | 19 | # Build results 20 | [Dd]ebug/ 21 | [Dd]ebugPublic/ 22 | [Rr]elease/ 23 | [Rr]eleases/ 24 | x64/ 25 | x86/ 26 | [Ww][Ii][Nn]32/ 27 | [Aa][Rr][Mm]/ 28 | [Aa][Rr][Mm]64/ 29 | bld/ 30 | [Bb]in/ 31 | [Oo]bj/ 32 | [Ll]og/ 33 | [Ll]ogs/ 34 | 35 | # Visual Studio 2015/2017 cache/options directory 36 | .vs/ 37 | # Uncomment if you have tasks that create the project's static files in wwwroot 38 | #wwwroot/ 39 | 40 | # Visual Studio 2017 auto generated files 41 | Generated\ Files/ 42 | 43 | # MSTest test Results 44 | [Tt]est[Rr]esult*/ 45 | [Bb]uild[Ll]og.* 46 | 47 | # NUnit 48 | *.VisualState.xml 49 | TestResult.xml 50 | nunit-*.xml 51 | 52 | # Build Results of an ATL Project 53 | [Dd]ebugPS/ 54 | [Rr]eleasePS/ 55 | dlldata.c 56 | 57 | # Benchmark Results 58 | BenchmarkDotNet.Artifacts/ 59 | 60 | # .NET 61 | project.lock.json 62 | project.fragment.lock.json 63 | artifacts/ 64 | 65 | # Tye 66 | .tye/ 67 | 68 | # ASP.NET Scaffolding 69 | ScaffoldingReadMe.txt 70 | 71 | # StyleCop 72 | StyleCopReport.xml 73 | 74 | # Files built by Visual Studio 75 | *_i.c 76 | *_p.c 77 | *_h.h 78 | *.ilk 79 | *.meta 80 | *.obj 81 | *.iobj 82 | *.pch 83 | *.pdb 84 | *.ipdb 85 | *.pgc 86 | *.pgd 87 | *.rsp 88 | *.sbr 89 | *.tlb 90 | *.tli 91 | *.tlh 92 | *.tmp 93 | *.tmp_proj 94 | *_wpftmp.csproj 95 | *.log 96 | *.vspscc 97 | *.vssscc 98 | .builds 99 | *.pidb 100 | *.svclog 101 | *.scc 102 | 103 | # Chutzpah Test files 104 | _Chutzpah* 105 | 106 | # Visual C++ cache files 107 | ipch/ 108 | *.aps 109 | *.ncb 110 | *.opendb 111 | *.opensdf 112 | *.sdf 113 | *.cachefile 114 | *.VC.db 115 | *.VC.VC.opendb 116 | 117 | # Visual Studio profiler 118 | *.psess 119 | *.vsp 120 | *.vspx 121 | *.sap 122 | 123 | # Visual Studio Trace Files 124 | *.e2e 125 | 126 | # TFS 2012 Local Workspace 127 | $tf/ 128 | 129 | # Guidance Automation Toolkit 130 | *.gpState 131 | 132 | # ReSharper is a .NET coding add-in 133 | _ReSharper*/ 134 | *.[Rr]e[Ss]harper 135 | *.DotSettings.user 136 | 137 | # TeamCity is a build add-in 138 | _TeamCity* 139 | 140 | # DotCover is a Code Coverage Tool 141 | *.dotCover 142 | 143 | # AxoCover is a Code Coverage Tool 144 | .axoCover/* 145 | !.axoCover/settings.json 146 | 147 | # Coverlet is a free, cross platform Code Coverage Tool 148 | coverage*.json 149 | coverage*.xml 150 | coverage*.info 151 | 152 | # Visual Studio code coverage results 153 | *.coverage 154 | *.coveragexml 155 | 156 | # NCrunch 157 | _NCrunch_* 158 | .*crunch*.local.xml 159 | nCrunchTemp_* 160 | 161 | # MightyMoose 162 | *.mm.* 163 | AutoTest.Net/ 164 | 165 | # Web workbench (sass) 166 | .sass-cache/ 167 | 168 | # Installshield output folder 169 | [Ee]xpress/ 170 | 171 | # DocProject is a documentation generator add-in 172 | DocProject/buildhelp/ 173 | DocProject/Help/*.HxT 174 | DocProject/Help/*.HxC 175 | DocProject/Help/*.hhc 176 | DocProject/Help/*.hhk 177 | DocProject/Help/*.hhp 178 | DocProject/Help/Html2 179 | DocProject/Help/html 180 | 181 | # Click-Once directory 182 | publish/ 183 | 184 | # Publish Web Output 185 | *.[Pp]ublish.xml 186 | *.azurePubxml 187 | # Note: Comment the next line if you want to checkin your web deploy settings, 188 | # but database connection strings (with potential passwords) will be unencrypted 189 | *.pubxml 190 | *.publishproj 191 | 192 | # Microsoft Azure Web App publish settings. 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2 | using System.Linq; 3 | using System.Text; 4 | 5 | namespace Metigator44.L01 6 | { 7 | internal class Program 8 | { 9 | static void Main(string[] args) 10 | { 11 | for (byte c = 0; c < 255; ++c) 12 | { 13 | char ch = (char)c; 14 | string dec = c.ToString().PadLeft(3, '0'); 15 | string hex = c.ToString("X"); 16 | string binary = Convert.ToString(c, 2).PadLeft(8, '0'); 17 | Console.WriteLine($"{dec,-12} {binary,-12} {hex,-12} {ch,-12}"); 18 | } 19 | 20 | Console.ReadKey(); 21 | } 22 | } 23 | } 24 | -------------------------------------------------------------------------------- /L02.EncodingAndUnicode/L02.EncodingAndUnicode.csproj: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | Exe 5 | net6.0 6 | enable 7 | enable 8 | 9 | 10 | 11 | -------------------------------------------------------------------------------- /L02.EncodingAndUnicode/Program.cs: -------------------------------------------------------------------------------- 1 | using Microsoft.VisualBasic; 2 | using System; 3 | using System.Collections; 4 | using System.Linq; 5 | using System.Text; 6 | 7 | namespace Metigator44.L02 8 | { 9 | internal class Program 10 | { 11 | static void Main(string[] args) 12 | { 13 | Encoding.RegisterProvider(CodePagesEncodingProvider.Instance); 14 | Encoding chinese = Encoding.GetEncoding("GB18030"); 15 | Console.WriteLine("大"); 16 | 17 | Task.Run(() => GetDataUTF8Format()); 18 | Console.ReadKey(); 19 | } 20 | 21 | static async Task GetDataAssciFormat() 22 | { 23 | var path = $"{Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}"; 24 | var filePath = $"{path}\\asciiNewsContent.txt"; 25 | 26 | using (var client = new HttpClient()) 27 | { 28 | Uri uri = new Uri("https://aljazeera.net/search/feed"); 29 | using (HttpResponseMessage response = await client.GetAsync(uri)) 30 | { 31 | var byteArray = await response.Content.ReadAsByteArrayAsync(); 32 | string result = Encoding.ASCII.GetString(byteArray); 33 | File.WriteAllText(filePath, result); 34 | } 35 | } 36 | } 37 | 38 | static async Task GetDataUTF8Format() 39 | { 40 | var path = $"{Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}"; 41 | var filePath = $"{path}\\utf8NewsContent.txt"; 42 | 43 | using (var client = new HttpClient()) 44 | { 45 | Uri uri = new Uri("https://aljazeera.net/search/feed"); 46 | using (HttpResponseMessage response = await client.GetAsync(uri)) 47 | { 48 | var byteArray = await response.Content.ReadAsByteArrayAsync(); 49 | string result = Encoding.UTF8.GetString(byteArray); 50 | File.WriteAllText(filePath, result); 51 | } 52 | } 53 | } 54 | } 55 | } 56 | -------------------------------------------------------------------------------- /L03.Instantiation/L03.Instantiation.csproj: -------------------------------------------------------------------------------- 1 |  2 | 3 | 4 | Exe 5 | net6.0 6 | preview 7 | true 8 | 9 | 10 | 11 | -------------------------------------------------------------------------------- /L03.Instantiation/Program.cs: -------------------------------------------------------------------------------- 1 | using System; 2 | using System.Runtime.InteropServices; 3 | 4 | namespace Metigator44.L03 5 | { 6 | internal class Program 7 | { 8 | static void Main(string[] args) 9 | { 10 | //UsingQuotedStringLiterals(); 11 | 12 | //UsingStringConstructor(); 13 | 14 | //UsingRepeatingCharacter(); 15 | 16 | //UsingPointerToSignedByte(); 17 | 18 | //UsingAPointerToCharacterArray(); 19 | 20 | //UsingConcatenation(); 21 | 22 | //UsingCallingMethodThatReturnsString(); 23 | 24 | //UsingFormattedString(); 25 | 26 | //UsingVerbatimWithStringInterpolation(); 27 | 28 | //UsingRawString(); 29 | 30 | Console.ReadKey(); 31 | } 32 | 33 | 34 | 35 | private static void UsingQuotedStringLiterals() 36 | { 37 | // Suited for strings that fit on a single line 38 | 39 | string str = "Metigator"; 40 | Console.WriteLine(str); 41 | } 42 | 43 | private static void UsingStringConstructor() 44 | { 45 | // [2] using String Constructor (array of characters) 46 | char[] letters = { 'M', 'e', 't', 'i', 'g', 'a', 't', 'o', 'r' }; 47 | string str = new string(letters); 48 | Console.WriteLine(str); 49 | } 50 | 51 | private static void UsingRepeatingCharacter() 52 | { 53 | // [3] // Create a string that consists of a character repeated 8 times. 54 | string str = new string('M', 8); 55 | Console.WriteLine(str); 56 | } 57 | 58 | private static void UsingPointerToSignedByte() 59 | { 60 | // [4] Create a string from a pointer to a signed byte array. 61 | // 'M' 'e' 't' 'i' 'g' 'a', 't', 'o' 'r' 62 | sbyte[] bytes = { 0x4D, 0x65, 0x74, 0x69, 0x67, 0x61, 0x74, 0x6F, 0x72 }; 63 | string str = null; 64 | // safe context (use pointer, allocation memory block, 65 | // call method using function pointer 66 | unsafe 67 | { 68 | // Pin the buffer to a fixed location in memory. 69 | fixed (sbyte* ptr = bytes) 70 | { 71 | str = new string(ptr); 72 | Console.WriteLine(str); 73 | 74 | } 75 | } 76 | } 77 | 78 | private static void UsingAPointerToCharacterArray() 79 | { 80 | // [5] Create a string from a pointer to a character array. 81 | char[] letters = { 'M', 'e', 't', 'i', 'g', 'a', 't', 'o', 'r' }; 82 | 83 | string str = null; 84 | unsafe 85 | { 86 | fixed (char* pchars = letters) 87 | { 88 | // Create a string from a pointer to a character array. 89 | str = new string(pchars); 90 | Console.WriteLine(str); 91 | } 92 | } 93 | } 94 | 95 | private static void UsingConcatenation() 96 | { 97 | // [5] Using concatenation 98 | string str1 = "Meti" + "gator"; 99 | string str2 = $"{"Meti"}{"gator"}"; // string interpolation 100 | 101 | Console.WriteLine($"str1 = {str1}"); 102 | Console.WriteLine($"str2 = {str2}"); 103 | } 104 | 105 | private static void UsingCallingMethodThatReturnsString() 106 | { 107 | 108 | string sentence = "I Love Metigator channel."; 109 | 110 | int startPos = sentence.IndexOf("Metigator"); // 7 111 | 112 | string str = sentence.Substring(startPos, 9); // string from 7, 113 | 114 | Console.WriteLine(str); 115 | 116 | } 117 | 118 | private static void UsingFormattedString() 119 | { 120 | // using formatted string will convert any object to string representation 121 | string customer = "Issam A"; 122 | DateTime shippingDate = DateTime.Now; // yyyy-MM-dd hh:mm 123 | DateTime expectedDelivery = shippingDate.AddDays(7); // yyyy-MM-dd hh:mm 124 | decimal shippingCost = 29.99m; 125 | 126 | string str = String.Format( 127 | "\nDear {0}.," + 128 | "\n\nAt {1:t} on {1:D}, the order is on its way to you" + 129 | "\nIt's expected to be delivered at {2:t} on {2:D}, the order is on its way to you" + 130 | "\nShipping cost {3:c}."+ 131 | "\n\t\t\tThanks for shopping with us!", 132 | 133 | customer, shippingDate, expectedDelivery, shippingCost); 134 | // 0 1 2 3 135 | Console.WriteLine(str); 136 | } 137 | 138 | private static void UsingVerbatimWithStringInterpolation() 139 | { 140 | string customer = "Issam A"; 141 | DateTime shippingDate = DateTime.Now; 142 | DateTime expectedDelivery = shippingDate.AddDays(7); 143 | decimal shippingCost = 29.99m; 144 | 145 | string str = $@"Dear {customer}, 146 | 147 | At {shippingDate:t} on {shippingDate:D}, the order is on its way to you 148 | It's expected to be delivered at {expectedDelivery:t} on {expectedDelivery:D}, the order is on its way to you 149 | Shipping cost {shippingCost:c}. 150 | Thanks for shopping with us!"; 151 | Console.WriteLine(str); 152 | } 153 | 154 | private static void UsingRawString() 155 | { 156 | // Raw string starting from C# 11.0 157 | string str = """ 158 | 166 | """; 167 | 168 | string str2 = """ this is a single line raw string"""; 169 | Console.WriteLine(str); 170 | Console.WriteLine(str2); 171 | 172 | } 173 | } 174 | } -------------------------------------------------------------------------------- /L04.L04.UnicodeAndStringComparison/L04.UnicodeAndStringComparison.csproj: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | Exe 5 | net6.0 6 | 7 | 8 | 9 | -------------------------------------------------------------------------------- /L04.L04.UnicodeAndStringComparison/Program.cs: -------------------------------------------------------------------------------- 1 | using System; 2 | using System.IO; 3 | 4 | namespace Metigator44.L04 5 | { 6 | internal class Program 7 | { 8 | static void Main(string[] args) 9 | { 10 | // Unicode character -> code point 11 | // Code point a = "\u0061"; 12 | // graphemes: multiple char object (base, combine) : a ̈ 13 | // Also we have single chars that represent the graphems ä 14 | 15 | 16 | StreamWriter sw = new StreamWriter(@".\output.txt"); 17 | string char1 = "\u0061"; // a 18 | string char2 = "\u0308"; // ̈ 19 | 20 | sw.WriteLine(char1); // a 21 | sw.WriteLine(char2); // ̈ 22 | 23 | 24 | string grapheme = "\u0061\u0308"; 25 | sw.WriteLine(grapheme); // ä 26 | 27 | 28 | string singleChar = "\u00e4"; 29 | sw.WriteLine(singleChar); // ä 30 | 31 | // representation are equal 32 | sw.WriteLine("{0} = {1} (Culture-sensitive): {2}", grapheme, singleChar, 33 | String.Equals(grapheme, singleChar, 34 | StringComparison.CurrentCulture)); // true 35 | 36 | sw.WriteLine("{0} = {1} (Ordinal): {2}", grapheme, singleChar, 37 | String.Equals(grapheme, singleChar, 38 | StringComparison.Ordinal)); // False 39 | 40 | sw.WriteLine("{0} = {1} (Normalized Ordinal): {2}", grapheme, singleChar, 41 | String.Equals(grapheme.Normalize(), 42 | singleChar.Normalize(), 43 | StringComparison.Ordinal)); // True 44 | sw.Close(); 45 | } 46 | 47 | } 48 | } -------------------------------------------------------------------------------- /L05.InternPool/L05.InternPool.csproj: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | Exe 5 | net6.0 6 | 7 | 8 | 9 | -------------------------------------------------------------------------------- /L05.InternPool/Program.cs: -------------------------------------------------------------------------------- 1 | using System; 2 | 3 | namespace Metigator44.L05 4 | { 5 | internal class Program 6 | { 7 | public static void Main(string[] args) 8 | { 9 | // RunStringLiteralVsObject(); 10 | // RunStringLiteralKey(); 11 | // RunStringLiteralWithStringObjectComparison(); 12 | RunStringIntern(); 13 | 14 | Console.ReadKey(); 15 | 16 | } 17 | 18 | public static void RunStringLiteralVsObject() 19 | { 20 | string s1 = "metigator"; // string literal 21 | string s2 = new string ("metigator"); // string object 22 | 23 | 24 | Console.WriteLine(s1 == s2); // true same content (string override equality value based) 25 | Console.WriteLine(s1.Equals(s2)); // true same content 26 | 27 | Console.WriteLine((Object)s1 == (Object)s2); // false two different reference 28 | Console.WriteLine(ReferenceEquals(s1, s2)); // false two different reference 29 | 30 | } 31 | 32 | public static void RunStringLiteralKey() 33 | { 34 | string s1 = "metigator"; // string literal 35 | string s2 = "aspnet"; // string literal 36 | string s3 = "meti" + "gator"; // string literal 37 | 38 | 39 | 40 | Console.WriteLine(s1 == s2); // false different content 41 | Console.WriteLine(ReferenceEquals(s1, s2)); // false two different reference 42 | 43 | 44 | Console.WriteLine(s1 == s3); // true same content 45 | Console.WriteLine(ReferenceEquals(s1, s3)); // true same reference 46 | } 47 | 48 | public static void RunStringLiteralWithStringObjectComparison() 49 | { 50 | string s1 = "metigator"; // string literal 51 | //string s11 = "metigator"; 52 | string s2 = new string("metigator"); // string object 53 | 54 | Console.WriteLine(s1 == s2); // true, same content 55 | 56 | Console.WriteLine(ReferenceEquals(s1, s2)); // false different reference 57 | 58 | } 59 | 60 | public static void RunStringIntern() 61 | { 62 | string s1 = "metigator"; // string literal 63 | 64 | string s2 = new string("metigator"); // string object 65 | 66 | string s3 = String.Intern(s2); // string literal 67 | 68 | Console.WriteLine(s1 == s2); // true, same content 69 | Console.WriteLine(ReferenceEquals(s1, s2)); // false different reference 70 | 71 | Console.WriteLine(s2 == s3); // true, same content 72 | Console.WriteLine(ReferenceEquals(s2, s3)); // false different reference 73 | 74 | Console.WriteLine(s1 == s3); // true, same content 75 | Console.WriteLine(ReferenceEquals(s1, s3)); // true, same reference 76 | 77 | 78 | string str = "xyz"; 79 | 80 | Console.WriteLine(str); 81 | 82 | } 83 | } 84 | } -------------------------------------------------------------------------------- /L06.StringMethods/L06.StringMethods.csproj: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | Exe 5 | net6.0 6 | 7 | 8 | 9 | -------------------------------------------------------------------------------- /L06.StringMethods/Program.cs: -------------------------------------------------------------------------------- 1 | using System; 2 | using System.Collections.Generic; 3 | 4 | namespace Metigator44.L06 5 | { 6 | internal class Program 7 | { 8 | public static void Main(string[] args) 9 | { 10 | //RunCopyTo(); 11 | // RunCompare(); 12 | // RunStringFound(); 13 | // RunStringFormat(); 14 | // RunStringIsNullOrEmpty(); 15 | // RunStringIsNullOrWhiteSpace(); 16 | // RunStringModify(); 17 | // RunToCase(); 18 | // RunTrim(); 19 | // RunToCharacterArray(); 20 | // RunSplit(); 21 | RunStringJoin(); 22 | Console.ReadKey(); 23 | } 24 | 25 | 26 | 27 | static void RunCopyTo() 28 | { 29 | string s1 = "metigator"; 30 | char[] characters = { 'f', 'u', 'l', 'l', ' ', 's', 't', 'a', 'c', 'k', ' ', 31 | '?', '?', '?', '?', '?', '?', '?', '?', '?'}; 32 | 33 | Console.WriteLine(characters); 34 | 35 | // copies count characters from the sourceIndex position of this instance 36 | // to the destinationIndex position of destination character array. 37 | 38 | s1.CopyTo(0, characters, 11, s1.Length); 39 | 40 | Console.WriteLine(characters); 41 | } 42 | 43 | static void RunCompare() 44 | { 45 | // ascii sort order (integer, capital, small) 46 | // a12Bc = 12Bac 47 | 48 | string s1 = "metigator"; 49 | string s2 = "Metigator"; 50 | 51 | // Compares two specified String objects and returns an integer 52 | // that indicates their relative position in the sort order. 53 | Console.WriteLine(string.Compare(s1, s2, true)); // 0 54 | Console.WriteLine(string.Compare(s1, s2, false)); // -1 55 | Console.WriteLine(string.Compare(s2, s1, false)); // 1 56 | } 57 | 58 | static void RunStringFound() 59 | { 60 | // ascii sort order (integer, capital, small) 61 | string s1 = "metigator"; 62 | 63 | // Returns whether a specified character occurs within this string. 64 | Console.WriteLine(s1.Contains("gato")); // true 65 | 66 | // starts with the specified character. 67 | Console.WriteLine(s1.StartsWith("meti")); // true 68 | 69 | // ends with the specified character. 70 | Console.WriteLine(s1.EndsWith("torx")); // false 71 | 72 | // Reports the zero-based index of the first occurrence 73 | Console.WriteLine(s1.IndexOf("tig")); //2 74 | } 75 | 76 | static void RunStringFormat() 77 | { 78 | var users = new List 79 | { 80 | new { Username = "user1", Since = new DateTime(2022, 7, 7) , Followers = 15053 }, 81 | new { Username = "user2", Since = new DateTime(2021, 5, 9) , Followers = 12046 }, 82 | new { Username = "user3", Since = new DateTime(2022, 11, 10) , Followers = 14027 } 83 | }; 84 | 85 | // Converts the value of objects to strings based on the 86 | // formats specified and inserts them into another string. 87 | var header = String.Format("{0,-12}{1,8}{2,12}\n", 88 | "Username", "Created At", "Followers"); 89 | 90 | Console.WriteLine(header); 91 | 92 | foreach (var user in users) 93 | Console.WriteLine(String.Format("{0,-12}{1,8:yyyy}{2,12:N0}\n", 94 | user.Username, user.Since, user.Followers)); 95 | 96 | } 97 | 98 | static void RunStringIsNullOrEmpty() 99 | { 100 | string s1 = "metigator"; 101 | string s2 = ""; 102 | string s3 = " "; 103 | string s4 = null; 104 | string s5 = String.Empty; 105 | 106 | // null or empty 107 | Console.WriteLine(String.IsNullOrEmpty(s1)); // false 108 | 109 | Console.WriteLine(String.IsNullOrEmpty(s2)); // true 110 | 111 | Console.WriteLine(String.IsNullOrEmpty(s3)); // false 112 | 113 | Console.WriteLine(String.IsNullOrEmpty(s4)); // true 114 | 115 | Console.WriteLine(String.IsNullOrEmpty(s5)); // true 116 | } 117 | 118 | static void RunStringIsNullOrWhiteSpace() 119 | { 120 | string s1 = "metigator"; 121 | string s2 = ""; 122 | string s3 = " "; 123 | string s4 = null; 124 | string s5 = String.Empty; 125 | 126 | // null or white spaces 127 | Console.WriteLine(String.IsNullOrWhiteSpace(s1)); // false 128 | 129 | Console.WriteLine(String.IsNullOrWhiteSpace(s2)); // true 130 | 131 | Console.WriteLine(String.IsNullOrWhiteSpace(s3)); // true 132 | 133 | Console.WriteLine(String.IsNullOrWhiteSpace(s4)); // true 134 | 135 | Console.WriteLine(String.IsNullOrWhiteSpace(s5)); // true 136 | } 137 | 138 | static void RunStringModify() 139 | { 140 | string s1 = "metior"; 141 | string s2 = "metizanor"; 142 | string s3 = "metixyzgator"; 143 | 144 | //Returns a new string in which a specified string is inserted at a 145 | //specified index position in this instance. 146 | s1 = s1.Insert(4, "gat"); 147 | Console.WriteLine(s1); // metigator 148 | 149 | // all occurrences the current string are replaced with 150 | // another specified Unicode character or String. 151 | s2 = s2.Replace("zan", "gat"); 152 | Console.WriteLine(s2); // metigator 153 | 154 | //Returns a new string in which a specified number of characters 155 | //from the current string are deleted. 156 | s3 = s3.Remove(4, 3); 157 | Console.WriteLine(s3); // metigator 158 | } 159 | 160 | static void RunToCase() 161 | { 162 | string s1 = "Metigator"; 163 | 164 | // Returns a copy of this string converted to uppercase 165 | // might produce culture specific output, 166 | // use it when user input string in their own language 167 | Console.WriteLine(s1.ToUpper()); 168 | 169 | // Returns a copy of this string converted to lowercase. 170 | // might produce culture specific output, 171 | // use it when user input string in their own language 172 | Console.WriteLine(s1.ToLower()); 173 | 174 | // Returns a copy of this string converted to lowercase. 175 | // use for non language specific data 176 | Console.WriteLine(s1.ToLowerInvariant()); 177 | 178 | // Returns a copy of this string converted to uppercase. 179 | // use for non language specific data 180 | Console.WriteLine(s1.ToUpperInvariant()); 181 | } 182 | 183 | static void RunTrim() 184 | { 185 | string s1 = " Metigator "; 186 | string s2 = "...Metigator...."; 187 | 188 | //Removes all leading and trailing occurrences 189 | Console.WriteLine("Trim(), Trim(char)"); 190 | Console.WriteLine(s1.Trim()); // "Metigator" 191 | Console.WriteLine(s2.Trim('.')); // "Metigator" 192 | 193 | //Removes all leading occurrences 194 | Console.WriteLine("TrimStart(), TrimStart(char)"); 195 | Console.WriteLine(s1.TrimStart()); // "Metigator " 196 | Console.WriteLine(s2.TrimStart('.'));// "Metigator...." 197 | 198 | //Removes all trailing occurrences 199 | Console.WriteLine("TrimEnd(), TrimEnd(char)"); 200 | Console.WriteLine(s1.TrimEnd());// " Metigator" 201 | Console.WriteLine(s2.TrimEnd('.')); // "...Metigator" 202 | } 203 | 204 | static void RunToCharacterArray() 205 | { 206 | string s1 = "metigator"; 207 | char[] characters; 208 | 209 | //Copies the characters in this instance to a Unicode character array. 210 | characters = s1.ToCharArray(); 211 | 212 | foreach (char ch in characters) 213 | Console.Write($" {ch}"); 214 | } 215 | 216 | static void RunSplit() 217 | { 218 | string s1 = "This is metigator channel"; 219 | 220 | // Returns a string array that contains the substrings 221 | // in this instance that are delimited by elements of 222 | // a specified string or Unicode character array. 223 | string[] words = s1.Split(" "); 224 | 225 | foreach (var word in words) 226 | Console.WriteLine(word); 227 | } 228 | 229 | static void RunStringJoin() 230 | { 231 | string[] values = { "Los Angeles", "1st Jan 1940", "15M" }; 232 | 233 | //Concatenates the elements of a specified array or the members 234 | //of a collection, using the specified separator between each 235 | //element or member. 236 | string commaSeparated = string.Join(',', values); 237 | 238 | Console.WriteLine(commaSeparated); // Los Angeles,1st Jan 1940,15M 239 | } 240 | 241 | 242 | } 243 | } -------------------------------------------------------------------------------- /Metigator44.sln: -------------------------------------------------------------------------------- 1 |  2 | Microsoft Visual Studio Solution File, Format Version 12.00 3 | # Visual Studio Version 17 4 | VisualStudioVersion = 17.3.32804.467 5 | MinimumVisualStudioVersion = 10.0.40219.1 6 | Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "L01.Ascii", "L01.Ascii\L01.Ascii.csproj", "{020E47EE-19B6-406B-8D64-91048B45E443}" 7 | EndProject 8 | Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "L02.EncodingAndUnicode", "L02.EncodingAndUnicode\L02.EncodingAndUnicode.csproj", "{8B07B2D9-C2A6-4A36-BE20-27D2738C4BEB}" 9 | EndProject 10 | Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "L03.Instantiation", "L03.Instantiation\L03.Instantiation.csproj", "{F7D48F69-AF50-4D22-9F97-CF82B89EF4E5}" 11 | EndProject 12 | Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "L04.UnicodeAndStringComparison", "L04.L04.UnicodeAndStringComparison\L04.UnicodeAndStringComparison.csproj", "{FADDBA36-DD25-4401-92C6-19E9E03AE3E3}" 13 | EndProject 14 | Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "L05.InternPool", "L05.InternPool\L05.InternPool.csproj", "{2CAF482A-E77F-4723-98F9-11B73A40DC66}" 15 | EndProject 16 | Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "L06.StringMethods", "L06.StringMethods\L06.StringMethods.csproj", "{A2E6A1AB-E188-48C3-AF99-FD60ADB09D97}" 17 | EndProject 18 | Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "L07.StringBuilderVsString", "L07.StringBuilderVsString\L07.StringBuilderVsString.csproj", "{446EE525-597B-4FE3-8593-86F262C312B9}" 19 | EndProject 20 | Global 21 | GlobalSection(SolutionConfigurationPlatforms) = preSolution 22 | Debug|Any CPU = Debug|Any CPU 23 | Release|Any CPU = Release|Any CPU 24 | EndGlobalSection 25 | GlobalSection(ProjectConfigurationPlatforms) = postSolution 26 | {020E47EE-19B6-406B-8D64-91048B45E443}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 27 | {020E47EE-19B6-406B-8D64-91048B45E443}.Debug|Any CPU.Build.0 = Debug|Any CPU 28 | {020E47EE-19B6-406B-8D64-91048B45E443}.Release|Any CPU.ActiveCfg = Release|Any CPU 29 | {020E47EE-19B6-406B-8D64-91048B45E443}.Release|Any CPU.Build.0 = Release|Any CPU 30 | {8B07B2D9-C2A6-4A36-BE20-27D2738C4BEB}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 31 | {8B07B2D9-C2A6-4A36-BE20-27D2738C4BEB}.Debug|Any CPU.Build.0 = Debug|Any CPU 32 | {8B07B2D9-C2A6-4A36-BE20-27D2738C4BEB}.Release|Any CPU.ActiveCfg = Release|Any CPU 33 | {8B07B2D9-C2A6-4A36-BE20-27D2738C4BEB}.Release|Any CPU.Build.0 = Release|Any CPU 34 | {F7D48F69-AF50-4D22-9F97-CF82B89EF4E5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 35 | {F7D48F69-AF50-4D22-9F97-CF82B89EF4E5}.Debug|Any CPU.Build.0 = Debug|Any CPU 36 | {F7D48F69-AF50-4D22-9F97-CF82B89EF4E5}.Release|Any CPU.ActiveCfg = Release|Any CPU 37 | {F7D48F69-AF50-4D22-9F97-CF82B89EF4E5}.Release|Any CPU.Build.0 = Release|Any CPU 38 | {FADDBA36-DD25-4401-92C6-19E9E03AE3E3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 39 | {FADDBA36-DD25-4401-92C6-19E9E03AE3E3}.Debug|Any CPU.Build.0 = Debug|Any CPU 40 | {FADDBA36-DD25-4401-92C6-19E9E03AE3E3}.Release|Any CPU.ActiveCfg = Release|Any CPU 41 | {FADDBA36-DD25-4401-92C6-19E9E03AE3E3}.Release|Any CPU.Build.0 = Release|Any CPU 42 | {2CAF482A-E77F-4723-98F9-11B73A40DC66}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 43 | {2CAF482A-E77F-4723-98F9-11B73A40DC66}.Debug|Any CPU.Build.0 = Debug|Any CPU 44 | {2CAF482A-E77F-4723-98F9-11B73A40DC66}.Release|Any CPU.ActiveCfg = Release|Any CPU 45 | {2CAF482A-E77F-4723-98F9-11B73A40DC66}.Release|Any CPU.Build.0 = Release|Any CPU 46 | {A2E6A1AB-E188-48C3-AF99-FD60ADB09D97}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 47 | {A2E6A1AB-E188-48C3-AF99-FD60ADB09D97}.Debug|Any CPU.Build.0 = Debug|Any CPU 48 | {A2E6A1AB-E188-48C3-AF99-FD60ADB09D97}.Release|Any CPU.ActiveCfg = Release|Any CPU 49 | {A2E6A1AB-E188-48C3-AF99-FD60ADB09D97}.Release|Any CPU.Build.0 = Release|Any CPU 50 | {446EE525-597B-4FE3-8593-86F262C312B9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU 51 | {446EE525-597B-4FE3-8593-86F262C312B9}.Debug|Any CPU.Build.0 = Debug|Any CPU 52 | {446EE525-597B-4FE3-8593-86F262C312B9}.Release|Any CPU.ActiveCfg = Release|Any CPU 53 | {446EE525-597B-4FE3-8593-86F262C312B9}.Release|Any CPU.Build.0 = Release|Any CPU 54 | EndGlobalSection 55 | GlobalSection(SolutionProperties) = preSolution 56 | HideSolutionNode = FALSE 57 | EndGlobalSection 58 | GlobalSection(ExtensibilityGlobals) = postSolution 59 | SolutionGuid = {7F1509DF-0621-4A2D-B8CC-16698B23B5F3} 60 | EndGlobalSection 61 | EndGlobal 62 | --------------------------------------------------------------------------------