Visual C++ .NET/Data Type/String

Compare strings for equality with ==

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str1 = "1";
   String^ str2 = "1";
   String^ str3 = str1;
   if (str1 == str2)
   {
      Console::WriteLine(" str1 == str2" );
   }
   if (str1 == str3)
   {
      Console::WriteLine(" str1 == str3" );
   }
   if (str1->Equals(str2))
   {
      Console::WriteLine(" str1 Equals str2" );
   }
   if (str1->Equals(str3))
   {
      Console::WriteLine(" str1 Equals str3");
   }
   if (String::ReferenceEquals(str1, str2))
   {
      Console::WriteLine(" str1 ReferenceEquals str2");
   }
   if (String::ReferenceEquals(str1, str3))
   {
      Console::WriteLine(" str1 ReferenceEquals str3");
   }
}

Compare strings for equality with String::Equals

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str1 = "1";
   String^ str2 = "1";
   String^ str3 = str1;
   if (str1 == str2)
   {
      Console::WriteLine(" str1 == str2" );
   }
   if (str1 == str3)
   {
      Console::WriteLine(" str1 == str3" );
   }
   if (str1->Equals(str2))
   {
      Console::WriteLine(" str1 Equals str2" );
   }
   if (str1->Equals(str3))
   {
      Console::WriteLine(" str1 Equals str3");
   }
   if (String::ReferenceEquals(str1, str2))
   {
      Console::WriteLine(" str1 ReferenceEquals str2");
   }
   if (String::ReferenceEquals(str1, str3))
   {
      Console::WriteLine(" str1 ReferenceEquals str3");
   }
}

Compare strings for equality with String::ReferenceEquals

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str1 = "1";
   String^ str2 = "1";
   String^ str3 = str1;
   if (str1 == str2)
   {
      Console::WriteLine(" str1 == str2" );
   }
   if (str1 == str3)
   {
      Console::WriteLine(" str1 == str3" );
   }
   if (str1->Equals(str2))
   {
      Console::WriteLine(" str1 Equals str2" );
   }
   if (str1->Equals(str3))
   {
      Console::WriteLine(" str1 Equals str3");
   }
   if (String::ReferenceEquals(str1, str2))
   {
      Console::WriteLine(" str1 ReferenceEquals str2");
   }
   if (String::ReferenceEquals(str1, str3))
   {
      Console::WriteLine(" str1 ReferenceEquals str3");
   }
}

Compare two strings with String::Compare

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str1 = "cat";
   String^ str2 = "cab";
   if (str1->CompareTo( str2 ) < 0)
   {
       Console::WriteLine(str1 + " is less than " + str2);
   }
      // For variety, use the static method.
   else if ( String::Compare(str1, str2) > 0 )
   {
       Console::WriteLine("{0} is less than {1}", str2, str1);
   }
   else if ( str1->CompareTo( str2 ) == 0)
   {
       Console::WriteLine("The strings are both equal, with value {0}.", str1);
   }
}

Convert back to a String using the String constructor that takes a Unicode character array.

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str = "A quick sly fox jumped over the lazy brown dog.";
   array<Char>^ character_array = str->ToCharArray();
   Console::WriteLine( str);
   for (int i = 0; i < character_array->Length; i++)
   {
      if ( character_array[i] >= L"a" && character_array[i] <= "z")
      {
        character_array[i] -= (L"a" - L"A");
      }
   }
   str = gcnew String(character_array);
   Console::WriteLine( str);
}

Convert String to char array

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str = "A quick sly fox jumped over the lazy brown dog.";
   array<Char>^ character_array = str->ToCharArray();
   Console::WriteLine( str);
   for (int i = 0; i < character_array->Length; i++)
   {
      if ( character_array[i] >= L"a" && character_array[i] <= "z")
      {
        character_array[i] -= (L"a" - L"A");
      }
   }
   str = gcnew String(character_array);
   Console::WriteLine( str);
}

Convert String to char pointer

 
#include "stdafx.h"
#include <vcclr.h>
#include <iostream>
using namespace std;
using namespace System;
int main()
{
   String^ s = "Testing String conversion to iostream.";
   pin_ptr<const wchar_t> ptr = PtrToStringChars(s);
   wcout << static_cast<const wchar_t*>( ptr ) << endl;
}

Convert text read from stdin to uppercase and write to stdout

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str;
   while ((str = Console::ReadLine()) != nullptr)
   {
      Console::WriteLine( str->ToUpper() );
   }
}

Create a copy, then concatenate new text

 
#include "stdafx.h"
using namespace System;
void main()
{
    String^ s1 = "This will ";
    String^ s2 = "be a ";
    String^ s3 = "String";
  // 
    String^ s4 = s2;  
    s4 = String::Concat(s4, "new ");
    Console::WriteLine(String::Concat(s1, s4, s3));
}

Create a String

 
#include "stdafx.h"
#using <mscorlib.dll>
using namespace System;
void main(void) {
    String^ Digits = "";
    for (int i=0; i<5; i++) {
        Digits = String::Concat(Digits, i.ToString("d"));
        Console::WriteLine(Digits);
    }
}

Create some strings

 
#include "stdafx.h"
using namespace System;
void main()
{
    String^ s1 = "This will ";
    String^ s2 = "be a ";
    String^ s3 = "String";
    Console::WriteLine(String::Concat(s1, s2, s3));
}

Insert into a string

 
#include "stdafx.h"
using namespace System;
void main()
{
    String^ s1 = "This will ";
    String^ s2 = "be a ";
    String^ s3 = "String";
    String^ s4 = s2;  
  // 
    String^ s6 = s3->Insert(3, "ange Str");
    Console::WriteLine(String::Concat(s1, s2, s6));
}

Output a string

 
#include "stdafx.h"
using namespace System;
void main(void)
{
    Console::WriteLine("Hello C++/CLI World");
}

Remove text from strings

 
#include "stdafx.h"
using namespace System;
void main()
{
    String^ s1 = "This will ";
    String^ s2 = "be a ";
    String^ s3 = "String";
    s1 = s1->Remove(4, 5);  
    s2 = s2->Remove(0, 3);  
    Console::WriteLine(String::Concat(s1, "is ", s2, s3));
}

Replace stuff in a concatenated string

 
#include "stdafx.h"
using namespace System;
void main()
{
    String^ s1 = "This will ";
    String^ s2 = "be a ";
    String^ s3 = "String";
    String^ s4 = s2;  
    // 
  String^ s5 = String::Concat(s1, s2, s3)->Replace("i", "*");
  Console::WriteLine(s5); 
}

Reverse a string

 
#include "stdafx.h"
using namespace System;
void main()
{
    array<int>^ a = gcnew array<int>(4);
    array<String^>^ b = gcnew array<String^>(4);
    for (int i = 0; i < a->Length; i++)
    {
        a[i] = i;
    }
    for (int i = 0; i < b->Length; i++)
    {
        b[i] = a[i].ToString();
    }
    for (int i = 0; i < b->Length; i++)
    {
        Console::WriteLine(b[i]);
    }
    Console::WriteLine();
    Array::Reverse(b);
    for (int i = 0; i < b->Length; i++)
    {
        Console::WriteLine(b[i]);
    }
}

String Literals

 
#include "stdafx.h"
using namespace System;
void main()
{
    String^ a = "Managed String";
    String^ b = L"Unicode String";
    Console::WriteLine(a);
    Console::WriteLine(b);
}

String operator plus

 
#include "stdafx.h"
using namespace System;
int main()
{
   String ^hrs = "Hours", ^mins = "Minutes";
   wchar_t separator = ":";
   int minutes = 56, hours = 1;
   Console::WriteLine( hrs + separator + " " + hours + "\n" + mins + separator + " " + minutes);
}

Use static method String::Compare to compare two strings

 

#include "stdafx.h"
using namespace System;
int main()
{
   String^ str1 = "cat";
   String^ str2 = "cab";
   if (str1->CompareTo( str2 ) < 0)
   {
       Console::WriteLine(str1 + " is less than " + str2);
   }
      // For variety, use the static method.
   else if ( String::Compare(str1, str2) > 0 )
   {
       Console::WriteLine("{0} is less than {1}", str2, str1);
   }
   else if ( str1->CompareTo( str2 ) == 0)
   {
       Console::WriteLine("The strings are both equal, with value {0}.", str1);
   }
}

Using string for each loop to output chars

 
#include "stdafx.h"
using namespace System;
int main()
{
   String^ str1 = "this is a test";
   for each (Char ch in str1)
   {
      Console::Write(ch);
   }
   Console::WriteLine();
}