Csharp/C Sharp/Data Types/String

Материал из .Net Framework эксперт
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A string can control a switch statement

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// A string can control a switch statement. 
 
using System; 
 
public class StringSwitch {  
  public static void Main() {  
    string[] strs = { "one", "two", "three", "two", "one" }; 
 
    foreach(string s in strs) { 
      switch(s) { 
        case "one": 
          Console.Write(1); 
          break; 
        case "two": 
          Console.Write(2); 
          break; 
        case "three": 
          Console.Write(3); 
          break; 
      } 
    } 
    Console.WriteLine(); 
 
  } 
}


create some strings

 
using System;
class MainClass {
    public static void Main() {
        
        string myString = "To be or not to be";
        string myString2 = "...\t that is the question";
        string myString3 = @"\t Friends, Romans, countrymen,
lend me your ears";
        // display the strings and their Length properties
        Console.WriteLine("myString = " + myString);
        Console.WriteLine("myString.Length = "
          + myString.Length);
        Console.WriteLine("myString2 = " + myString2);
        Console.WriteLine
         ("myString2.Length = " + myString2.Length);
        Console.WriteLine("myString3 = " + myString3);
        Console.WriteLine
          ("myString3.Length = " + myString3.Length);    
    }
}


Creating Strings

using System;

  public class CreatingStrings
  {
    static void Main(string[] args)
    {
      char MyChar = "A";
      MyChar = (char)65;
      char[] MyChar2 = {"H","e","l","l","o","\0"};
      char[] MyChar3 = new char[6];
      MyChar3[0] = "H";
      MyChar3[1] = "e";
      MyChar3[2] = "l";
      MyChar3[3] = "l";
      MyChar3[4] = "o";
      MyChar3[5] = "\0";
    }
  }


Decoding a Base64-encoded Binary

using System;
using System.Data;
using System.Text.RegularExpressions;
using System.Text;
class Class1{
        static void Main(string[] args){
             Console.WriteLine(Base64EncodeBytes(new byte[5] {45,34,23,54,38}));
         }
    public static string Base64EncodeBytes(byte[] inputBytes) 
    {
      // Each 3 byte sequence in inputBytes must be converted to a 4 byte sequence 
      long arrLength = (long)(4.0d * inputBytes.Length / 3.0d);
      if ((arrLength  % 4) != 0) 
      {
        // increment the array lenght to the next multiple of 4 if it is not already divisible by 4
        arrLength += 4 - (arrLength % 4);
      }
    
      char[] encodedCharArray = new char[arrLength];
      Convert.ToBase64CharArray(inputBytes, 0, inputBytes.Length, encodedCharArray, 0);
      
      return (new string(encodedCharArray));
    }      
}


Demonstrate Concat()

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// Demonstrate Concat(). 
 
using System; 
 
public class ConcatDemo1 { 
  public static void Main() { 
 
    string result = String.Concat("This ", "is ", "a ", 
                                  "test ", "of ", "the ", 
                                  "String ", "class."); 
 
    Console.WriteLine("result: " + result); 
 
  } 
}


Demonstrate Concat() 2

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// Demonstrate Concat(). 
 
using System; 
 
public class ConcatDemo { 
  public static void Main() { 
 
    string result = String.Concat("hi ", 10, " ", 
                                   20.0, " ", 
                                   false, " ", 
                                   23.45M); 
 
    Console.WriteLine("result: " + result); 
  } 
}


Demonstrate escape sequences in strings.

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Demonstrate escape sequences in strings. 
 
using System; 
 
public class StrDemo {    
  public static void Main() {    
    Console.WriteLine("Line One\nLine Two\nLine Three"); 
    Console.WriteLine("One\tTwo\tThree"); 
    Console.WriteLine("Four\tFive\tSix"); 
 
    // embed quotes 
    Console.WriteLine("\"Why?\", he asked."); 
  }    
}


Demonstrate string arrays

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Demonstrate string arrays.  
 
using System; 
 
public class StringArrays {  
  public static void Main() {  
    string[] str = { "This", "is", "a", "test." };  
  
    Console.WriteLine("Original array: ");  
    for(int i=0; i < str.Length; i++) 
      Console.Write(str[i] + " ");  
    Console.WriteLine("\n");  
  
    // change a string  
    str[1] = "was";  
    str[3] = "test, too!";  
  
    Console.WriteLine("Modified array: "); 
    for(int i=0; i < str.Length; i++) 
      Console.Write(str[i] + " ");  
  }  
}


Demonstrate verbatim literal strings

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Demonstrate verbatim literal strings. 
 
using System; 
 
public class Verbatim {    
  public static void Main() {    
    Console.WriteLine(@"This is a verbatim 
string literal 
that spans several lines. 
"); 
    Console.WriteLine(@"Here is some tabbed output: 
1  2  3  4 
5  6  7  8 
"); 
    Console.WriteLine(@"Programmers say, ""I like C#."""); 
  }    
}


Display a string in reverse by using recursion

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// Display a string in reverse by using recursion. 
 
using System; 
  
class RevStr { 
 
  // Display a string backwards. 
  public void displayRev(string str) { 
    if(str.Length > 0)  
      displayRev(str.Substring(1, str.Length-1)); 
    else  
      return; 
 
    Console.Write(str[0]); 
  } 
} 
 
public class RevStrDemo { 
  public static void Main() {   
    string s = "this is a test"; 
    RevStr rsOb = new RevStr(); 
 
    Console.WriteLine("Original string: " + s); 
 
    Console.Write("Reversed string: "); 
    rsOb.displayRev(s); 
 
    Console.WriteLine(); 
  } 
}


Display the digits of an integer using words

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Display the digits of an integer using words. 
 
using System; 
 
public class ConvertDigitsToWords {   
  public static void Main() { 
    int num; 
    int nextdigit; 
    int numdigits; 
    int[] n = new int[20]; 
     
    string[] digits = { "zero", "one", "two", 
                        "three", "four", "five", 
                        "six", "seven", "eight", 
                        "nine" }; 
 
    num = 1908; 
 
    Console.WriteLine("Number: " + num); 
 
    Console.Write("Number in words: "); 
     
    nextdigit = 0; 
    numdigits = 0; 
   
    /* Get individual digits and store in n. 
       These digits are stored in reverse order. */ 
    do { 
      nextdigit = num % 10; 
      n[numdigits] = nextdigit; 
      numdigits++; 
      num = num / 10; 
    } while(num > 0); 
    numdigits--; 
 
    // display words 
    for( ; numdigits >= 0; numdigits--) 
      Console.Write(digits[n[numdigits]] + " "); 
 
    Console.WriteLine(); 
  }   
}


Extracting Substrings

/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 */
using System;
namespace Client.Chapter_6___Strings
{
  public class ExtractingSubstrings
  {
    static void Main(string[] args)
    {
      string MyClasses = "Math 101 - Algebra";
      string MySubstring = MyClasses.Substring(6);
      Console.WriteLine(MySubstring);
    }
  }
}


From Base 64 Decode String

using System;
using System.Data;
using System.Text.RegularExpressions;
using System.Text;
class Class1{
        static void Main(string[] args){
            foreach (byte b in Base64DecodeString("AAAA"))
                Console.WriteLine(b);
         }
    public static byte[] Base64DecodeString(string inputStr) 
    {
      byte[] encodedByteArray = Convert.FromBase64CharArray(inputStr.ToCharArray(), 0, inputStr.Length);
      return (encodedByteArray);
    }   
}


Illustrates the use of strings 1

/*
Mastering Visual C# .NET
by Jason Price, Mike Gunderloy
Publisher: Sybex;
ISBN: 0782129110
*/
/*
  Example2_9.cs illustrates the use of strings
*/
public class Example2_9
{
  public static void Main()
  {
    string helloWorld = "Hello World!";
    System.Console.WriteLine(helloWorld);
    helloWorld = "Hello World" + " from C#!";
    System.Console.WriteLine(helloWorld);
    helloWorld = "Hello World" + "\n from C#!";
    System.Console.WriteLine(helloWorld);
    const double Pi = 3.14159;
    System.Console.WriteLine("Pi = " + Pi);
  }
}


Introduce string

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Introduce string. 
 
using System; 
 
public class StringDemo {  
  public static void Main() {  
 
    char[] charray = {"A", " ", "s", "t", "r", "i", "n", "g", "." }; 
    string str1 = new string(charray); 
    string str2 = "Another string."; 
 
    Console.WriteLine(str1); 
    Console.WriteLine(str2); 
  }  
}


Is Palindrome

 
using System;
using System.Text;
public class MainClass {
    public static bool IsPalindrome(string s) {
        int iLength, iHalfLen;
        iLength = s.Length - 1;
        iHalfLen = iLength / 2;
        for (int i = 0; i <= iHalfLen; i++) {
            if (s.Substring(i, 1) !=
                s.Substring(iLength - i, 1)) {
                return false;
            }
        }
        return true;
    }
    static void Main(string[] args) {
        string[] sa = new string[]{"level", "minim", "radar"};
        foreach (string v in sa)
            Console.WriteLine("{0}\t{1}",v, IsPalindrome(v));
    }
}


Joining Strings

/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 */
using System;
namespace Client.Chapter_6___Strings
{
  public class JoiningStrings
  {
    static void Main(string[] args)
    {
      string MyString = "Hello";
      string MyString2 = "World";
      string JoinedString = MyString + MyString2;
      Console.WriteLine(JoinedString);
      string[] A = new string[2] {
        "Hello", "World"
      };
      string Joined = string.Join(" ", A);
      Console.WriteLine(Joined);
    }
  }
}


Lexical Details

using System;
public class StringVerbatimStrings
{
    public static void Main()
    {
        string s = @"
        C: Hello, Miss?
        O: What do you mean, "Miss"?
        C: I"m Sorry, I have a cold. I wish to make a complaint.";
        Console.WriteLine(s);
    }
}


Padding Strings

using System;

  public class PaddingStrings
  {
    static void Main(string[] args)
    {
      string MyString = "Hello World";
      Console.WriteLine(MyString.PadLeft(5));
    }
  }


Removing Characters

using System;

  public class RemovingCharacters
  {
    static void Main(string[] args)
    {
      string MyString = "Hello UnderWorld";
      Console.WriteLine(MyString.Remove(7, 5));
    }
  }


Some string operations

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Some string operations.  
  
using System;  
  
public class StrOps {   
  public static void Main() {   
    string str1 =  
      "When it comes to .NET programming, C# is #1.";   
    string str2 = string.Copy(str1);  
    string str3 = "C# strings are powerful.";   
    string strUp, strLow; 
    int result, idx;  
  
    Console.WriteLine("str1: " + str1); 
 
    Console.WriteLine("Length of str1: " +   
                       str1.Length);   
   
    // create upper- and lowercase versions of str1  
    strLow = str1.ToLower(); 
    strUp =  str1.ToUpper(); 
    Console.WriteLine("Lowercase version of str1:\n    " + 
                      strLow); 
    Console.WriteLine("Uppercase version of str1:\n    " + 
                      strUp); 
 
    Console.WriteLine();   
 
    // display str1, one char at a time.  
    Console.WriteLine("Display str1, one char at a time."); 
    for(int i=0; i < str1.Length; i++)  
      Console.Write(str1[i]);   
    Console.WriteLine("\n");   
 
    // compare strings 
    if(str1 == str2)   
      Console.WriteLine("str1 == str2");   
    else   
      Console.WriteLine("str1 != str2");   
   
    if(str1 == str3)   
      Console.WriteLine("str1 == str3");   
    else   
      Console.WriteLine("str1 != str3");   
  
    result = str1.rupareTo(str3);  
    if(result == 0)  
      Console.WriteLine("str1 and str3 are equal");  
    else if(result < 0)  
      Console.WriteLine("str1 is less than str3");  
    else  
      Console.WriteLine("str1 is greater than str3");  
  
    Console.WriteLine();   
 
    // assign a new string to str2  
    str2 = "One Two Three One";  
  
    // search string 
    idx = str2.IndexOf("One");  
    Console.WriteLine("Index of first occurrence of One: " + idx);  
    idx = str2.LastIndexOf("One");  
    Console.WriteLine("Index of last occurrence of One: " + idx);  
      
  }   
}


string: Changing Characters

using System;

  public class ChangingCharacters
  {
    static void Main(string[] args)
    {
      string MyString = "Miami, Dolphins";
      Console.WriteLine(MyString);
      MyString.ToUpper();
      Console.WriteLine(MyString);
      MyString.ToLower();
      Console.WriteLine(MyString);
    }
  }


String Concatenation 2

/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 */
using System;
namespace Client.Chapter_6___Strings
{
  public class StringConcatenation2
  {
    static void Main(string[] args)
    {
      Console.WriteLine("Enter Your Password?");
      string UserPassword = Console.ReadLine();
      string Password = "Victory";
      if(Password.rupareTo(UserPassword) == 0)
        {
          Console.WriteLine("Bad Password");
        }
      Console.WriteLine("Good Password!");
    }
  }
}


String copy

/*
Learning C# 
by Jesse Liberty
Publisher: O"Reilly 
ISBN: 0596003765
*/
 using System;
 namespace StringManipulation
 {
    public class TesterStringManipulationCopy
    {
       public void Run()
       {
           string s1 = "abcd";
           string s2 = "ABCD";
           // the string copy method
           string s5 = string.Copy(s2);
           Console.WriteLine(
               "s5 copied from s2: {0}", s5);
           // use the overloaded operator
           string s6 = s5;
           Console.WriteLine("s6 = s5: {0}", s6);
       }
       static void Main()
       {
          TesterStringManipulationCopy t = new TesterStringManipulationCopy();
          t.Run();
       }
    }
 }


String Copy, End With and Insert

/*
Learning C# 
by Jesse Liberty
Publisher: O"Reilly 
ISBN: 0596003765
*/
 using System;
 namespace StringManipulation
 {
    public class TesterStringCopyEndWithInsert
    {
       public void Run()
       {
           string s1 = "abcd";
           string s2 = "ABCD";
           string s3 = @"Liberty Associates, Inc.
                 provides custom .NET development,
                 on-site Training and Consulting";
           // the string copy method
           string s5 = string.Copy(s2);
           Console.WriteLine(
               "s5 copied from s2: {0}", s5);
           // Two useful properties: the index and the length
           Console.WriteLine(
               "\nString s3 is {0} characters long. ",
               s5.Length);
           Console.WriteLine(
               "The 5th character is {0}\n", s3[4]);
           // test whether a string ends with a set of characters
           Console.WriteLine("s3:{0}\nEnds with Training?: {1}\n",
               s3,
               s3.EndsWith("Training") );
           Console.WriteLine(
               "Ends with Consulting?: {0}",
               s3.EndsWith("Consulting"));
           // return the index of the substring
           Console.WriteLine(
               "\nThe first occurrence of Training ");
           Console.WriteLine ("in s3 is {0}\n",
               s3.IndexOf("Training"));
           // insert the word excellent before "training"
           string s10 = s3.Insert(101,"excellent ");
           Console.WriteLine("s10: {0}\n",s10);
           // you can combine the two as follows:
           string s11 = s3.Insert(s3.IndexOf("Training"),
               "excellent ");
           Console.WriteLine("s11: {0}\n",s11);
       }
       [STAThread]
       static void Main()
       {
          TesterStringCopyEndWithInsert t = new TesterStringCopyEndWithInsert();
          t.Run();
       }
    }
 }


String Interning

using System;
public class StringInterning
{
    public static void Main()
    {
        string s1 = "Hello";
        string s2 = "Hello";
        string s3 = "Hello".Substring(0, 4) + "o";
        
        Console.WriteLine("Str == : {0}", s1 == s2);
        Console.WriteLine("Ref == : {0}", (object) s1 == (object) s2);
        
        Console.WriteLine("Str == : {0}", s1 == s3);
        Console.WriteLine("Ref == : {0}", (object) s1 == (object) s3);
    }
}


String Manipulation

/*
Learning C# 
by Jesse Liberty
Publisher: O"Reilly 
ISBN: 0596003765
*/
 using System;
 namespace StringManipulation
 {
    public class TesterStringManipulationCompare
    {
       public void Run()
       {
           // create some strings to work with
           string s1 = "abcd";
           string s2 = "ABCD";
           int result;  // hold the results of comparisons
           // compare two strings, case sensitive
           result = string.rupare(s1, s2);
           Console.WriteLine(
               "compare s1: {0}, s2: {1}, result: {2}\n",
               s1, s2, result);
           // overloaded compare, takes boolean "ignore case"
           //(true = ignore case)
           result = string.rupare(s1,s2, true);
           Console.WriteLine("Compare insensitive. result: {0}\n",
               result);
       }
       [STAThread]
       static void Main()
       {
          TesterStringManipulationCompare t = new TesterStringManipulationCompare();
          t.Run();
       }
    }
 }


String Manipulation Concatenate

/*
Learning C# 
by Jesse Liberty
Publisher: O"Reilly 
ISBN: 0596003765
*/
 using System;
 namespace StringManipulation
 {
    public class TesterStringManipulationConcat
    {
       public void Run()
       {
           string s1 = "abcd";
           string s2 = "ABCD";
           // concatenation method
           string s3 = string.Concat(s1,s2);
           Console.WriteLine(
               "s3 concatenated from s1 and s2: {0}", s3);
           // use the overloaded operator
           string s4 = s1 + s2;
           Console.WriteLine(
               "s4 concatenated from s1 + s2: {0}", s4);
       }
       static void Main()
       {
          TesterStringManipulationConcat t = new TesterStringManipulationConcat();
          t.Run();
       }
    }
 }


Strings: Regular Expressions

using System;
using System.Text.RegularExpressions;
public class RegularExpressions
{
    public static void Main()
    {
        string s = "Oh, I hadn"t thought of that";
        Regex regex = new Regex(@" |, ");
        char[] separators = new char[] {" ", ","};
        
        foreach (string sub in regex.Split(s))
        {
            Console.WriteLine("Word: {0}", sub);
        }
    }
}


String To Char Array

using System;
public class StringToCharArray
{
    public static void Main()
    {
        string s = "Test String";
        
        for (int index = 0; index < s.Length; index++)
            Console.WriteLine("Char: {0}", s[index]);
    }
}


Substring demo

/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 */
using System;
namespace Client.Chapter_6___Strings
{
  public class Substrings
  {
    static void Main(string[] args)
    {
      string[] FootballTeams = new string[3] {
        "Miami, Dolphins", "Oakland, Raiders", "Seattle, Seahawks"
      };
      foreach (string s in FootballTeams)
      {
        if (s.StartsWith("Miami"))
          Console.WriteLine("Awesome!");
        else
          Console.WriteLine("Bummer Dude!");
      }
    }
  }
}


Trimming and padding

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// Trimming and padding. 
  
using System;  
  
public class TrimPadDemo {  
  public static void Main() {  
    string str = "test"; 
 
    Console.WriteLine("Original string: " + str); 
     
    // Pad on left with spaces. 
    str = str.PadLeft(10); 
    Console.WriteLine("|" + str + "|"); 
 
    // Pad on right with spaces. 
    str = str.PadRight(20); 
    Console.WriteLine("|" + str + "|"); 
 
    // Trim spaces. 
    str = str.Trim(); 
    Console.WriteLine("|" + str + "|"); 
 
    // Pad on left with #s. 
    str = str.PadLeft(10, "#"); 
    Console.WriteLine("|" + str + "|"); 
 
    // Pad on right with #s. 
    str = str.PadRight(20, "#"); 
    Console.WriteLine("|" + str + "|"); 
 
    // Trim #s. 
    str = str.Trim("#"); 
    Console.WriteLine("|" + str + "|"); 
  } 
}


Trimming String Spaces

/*
 * C# Programmers Pocket Consultant
 * Author: Gregory S. MacBeth
 * Email: gmacbeth@comporium.net
 * Create Date: June 27, 2003
 * Last Modified Date:
 */
using System;
namespace Client.Chapter_6___Strings
{
  public class TrimmingSpaces
  {
    static void Main(string[] args)
    {
      string MyString = "   Hello, World !  ";
      MyString.TrimStart();
      Console.WriteLine(MyString);
      MyString.TrimEnd();
      Console.WriteLine(MyString);
      MyString.Trim(char.Parse("!"));
      Console.WriteLine(MyString);
    }
  }
}


Use Substring() 1

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Use Substring(). 
 
using System; 
 
public class SubStr {  
  public static void Main() {  
    string orgstr = "C# makes strings easy."; 
 
    // construct a substring 
    string substr = orgstr.Substring(5, 12); 
     
    Console.WriteLine("orgstr: " + orgstr); 
    Console.WriteLine("substr: " + substr); 
 
  }  
}


Use Substring() 2

/*
C#: The Complete Reference 
by Herbert Schildt 
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/

// Use Substring(). 
  
using System;  
  
public class SubstringDemo {  
  public static void Main() {  
    string str = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; 
 
    Console.WriteLine("str: " + str); 
     
    Console.Write("str.Substring(15): "); 
    string substr = str.Substring(15); 
    Console.WriteLine(substr); 
 
    Console.Write("str.Substring(0, 15): "); 
    substr = str.Substring(0, 15); 
    Console.WriteLine(substr); 
  } 
}


use the addition operator (+) to concatenate strings

 
using System;
class MainClass {
    public static void Main() {
        
        string myString6 = "To be, " + "or not to be";
        Console.WriteLine("\"To be, \" + \"or not to be\" = " + myString6);
    
    }
}


use the Concat() method to concatenate strings

 
using System;
class MainClass {
    public static void Main() {
        
        string myString4 = String.Concat("Friends, ", "Romans");
        Console.WriteLine("String.Concat(\"Friends, \", \"Romans\") = " + myString4);
        string myString5 = String.Concat("Friends, ", "Romans, ", "and countrymen");
        Console.WriteLine("String.Concat(\"Friends, \", \"Romans, \", " +"\"and countrymen\") = " + myString5);
    
    }
}


use the Copy() method to copy a string

 
using System;
class MainClass {
    public static void Main() {
        string myString4 = String.Concat("Friends, ", "Romans");
        Console.WriteLine("myString4 = " + myString4);
        Console.WriteLine("Copying myString4 to myString7 using Copy()");
        string myString7 = String.Copy(myString4);
        Console.WriteLine("myString7 = " + myString7);
    
    }
}


use the Join() method to join strings

 
using System;
class MainClass {
    public static void Main() {
        string[] myStrings = {"To", "be", "or", "not","to", "be"};
        string myString9 = String.Join(".", myStrings);
        Console.WriteLine("myString9 = " + myString9);
    
    }
}


use the PadLeft() and PadRight() methods to align strings

 
using System;
class MainClass {
    public static void Main() {
        string[] myStrings = {"To", "be", "or", "not","to", "be"};
        string myString = String.Join(".", myStrings);        
        string myString14 = "(" + myString.PadLeft(20) + ")";
        Console.WriteLine(""(" + myString.PadLeft(20)+ ")" = " + myString14);
        string myString15 = "(" + myString.PadLeft(20, ".")
        + ")";
        Console.WriteLine(""(" + myString.PadLeft(20, ".") =" + myString15);
        string myString16 = "(" + myString.PadRight(20) + ")";
        Console.WriteLine(""(" + myString.PadRight(20) + ")" =" + myString16);
        string myString17 = "(" +
        myString.PadRight(20, ".") + ")";
        Console.WriteLine(""(" +myString.PadRight(20, ".") + ")" = " + myString17);
    
    }
}


use the StartsWith() and EndsWith() methods to check if a string contains a specified substring at the start and end

 

using System;
class MainClass {
    public static void Main() {
        string[] myStrings = {"To", "be", "or", "not","to", "be"};
        string myString = String.Join(".", myStrings);        
        Console.WriteLine("myString = " + myString);
        if (myString.StartsWith("To")) {
            Console.WriteLine("myString starts with \"To\"");
        }
        if (myString.EndsWith("be")) {
            Console.WriteLine("myString ends with \"be\"");
        }
    
    }
}


use the Substring() method to retrieve substrings

 
using System;
class MainClass {
    public static void Main() {
        string[] myStrings = {"To", "be", "or", "not","to", "be"};
        string myString = String.Join(".", myStrings);        
        string myString21 = myString.Substring(3);
        Console.WriteLine("myString.Substring(3) = " + myString21);
        string myString22 = myString.Substring(3, 2);
        Console.WriteLine("myString.Substring(3, 2) = " + myString22);
        string myString23 = myString.ToUpper();
        Console.WriteLine("myString.ToUpper() = " + myString23);
        string myString24 = myString.ToLower();
        Console.WriteLine("myString.ToLower() = " + myString24);
    }
}


use the Trim(), TrimStart(), and TrimEnd() methods to trim strings

 
using System;
class MainClass {
    public static void Main() {
        string myString18 = "(" +"  Whitespace  ".Trim() + ")";
        Console.WriteLine(""(" +\"  Whitespace  \".Trim() + ")" = " + myString18);
        string myString19 = "(" + "  Whitespace  ".TrimStart() + ")";
        Console.WriteLine(""(" +\"  Whitespace  \".TrimStart() + ")" = " + myString19);
        string myString20 = "(" + "  Whitespace  ".TrimEnd() + ")";
        Console.WriteLine(""(" +\"  Whitespace  \".TrimEnd() + ")" = " + myString20);
    
    }
}


Using Strings

using System;

  public class UsingStrings
  {
    static void Main(string[] args)
    {
      string MyString = "Hello World";
      string Path = @"c:\Program Files";
      string Path2 = "c:\\Program Files";
      string Name = "Joe";
    }
  }