Imports System
Imports System.Globalization
Imports System.Text

Namespace PerformanceLibrary

   Class MakeString
   
      Shared currentCulture As CultureInfo = CultureInfo.CurrentCulture

      Shared Sub Main()
      
         ' Loops 1 through 4 violate this rule.
         Loop1()
         Loop2()
         Loop3()
         Loop4()
         Loop5()

      End Sub

      Shared Sub Loop1()
      
         Dim digits As String = String.Empty
         For I As Integer = 0 To 9
            digits = String.Concat(digits, I.ToString(currentCulture))
         Next I
         Console.WriteLine(digits)

      End Sub

      ' This method violates the rule but 
      ' the violation should be excluded.
      Shared Sub Loop2()
      
         Dim digits As String = String.Empty
         For I As Integer = 0 To 9
            digits = String.Concat(digits, I.ToString(currentCulture))
            Console.WriteLine(digits)
         Next I

      End Sub

      Shared Sub Loop3()
      
         Dim digits As String = String.Empty
         For I As Integer = 0 To 9
            digits = digits & I.ToString(currentCulture)
         Next I
         Console.WriteLine(digits)

      End Sub

      Shared Sub Loop4()
      
         Dim digits As String = String.Empty
         For I As Integer = 0 To 9
            digits += i.ToString(currentCulture)
         Next I
         Console.WriteLine(digits)

      End Sub

      ' This method does not cause a violation of the rule.
      Shared Sub Loop5()
      
         Dim digits As New StringBuilder()
         For I As Integer = 0 To 9
            digits.Append(I.ToString(currentCulture))
         Next I
         Console.WriteLine(digits)

      End Sub

   End Class

End Namespace

using System;
using System.Globalization;
using System.Text;

namespace PerformanceLibrary
{
   class MakeString
   {
      static CultureInfo currentCulture = CultureInfo.CurrentCulture;

      static void Main()
      {
         // Loops 1 through 4 violate this rule.
         Loop1();
         Loop2();
         Loop3();
         Loop4();
         Loop5();
      }

      static void Loop1()
      {
         string digits = string.Empty;
         for(int i = 0; i < 10; i++)
         {
            digits = String.Concat(digits, i.ToString(currentCulture));
         }
         Console.WriteLine(digits);
      }
      
      // This method violates the rule but 
      // the violation should be excluded.
      static void Loop2()
      {
         string digits = string.Empty;
         for(int i = 0; i < 10; i++)
         {
            digits = String.Concat(digits, i.ToString(currentCulture));
            Console.WriteLine(digits);
         }
      }

      static void Loop3()
      {
         string digits = string.Empty;
         for(int i = 0; i < 10; i++)
         {
            digits = digits + i.ToString(currentCulture);
         }
         Console.WriteLine(digits);
      }

      static void Loop4()
      {
         string digits = string.Empty;
         for(int i = 0; i < 10; i++)
         {
            digits += i.ToString(currentCulture);
         }
         Console.WriteLine(digits);
      }

      // This method does not cause a violation of the rule.
      static void Loop5()
      {
         StringBuilder digits = new StringBuilder();
         for(int i = 0; i < 10; i++)
         {
            digits.Append(i.ToString(currentCulture));
         }
         Console.WriteLine(digits.ToString());
      }
   }
}