StringBuilder sb = new StringBuilder("Ciao"); 

  sb.Append(" da "); sb.Append("Marco");

  

Console.WriteLine(sb.ToString()); 

  ////////////////////////////// 

  string string2 = "ciao " + " da " + "marco" + 
  " e " + "alessio"; 

  Console.WriteLine(string2);

  IL_0000: ldarg.0 

  IL_0001: call instance void [mscorlib]System.Object::.ctor() 

  IL_0006: ldstr "Ciao" 

  IL_000b: newobj instance void [mscorlib]System.Text.StringBuilder::.ctor(string) 
  

  IL_0010: stloc.0 IL_0011: ldloc.0 IL_0012: ldstr " da " 

  IL_0017: callvirt instance class [mscorlib]System.Text.StringBuilder [mscorlib]System.Text.StringBuilder::Append(string) 
  

  IL_001c: pop IL_001d: ldloc.0 

  IL_001e: ldstr "Marco" 

  IL_0023: callvirt instance class [mscorlib]System.Text.StringBuilder [mscorlib]System.Text.StringBuilder::Append(string) 
  

  IL_0028: pop 

  IL_0029: ldloc.0 IL_002a: callvirt instance string [mscorlib]System.Text.StringBuilder::ToString() 
  

  IL_002f: call void [mscorlib]System.Console::WriteLine(string) <b>

  IL_0034: ldstr "ciao da marco e alessio"</b> 

  IL_0039: stloc.1 

  IL_003a: ldloc.1 

  IL_003b: call void [mscorlib]System.Console::WriteLine(string) 

  IL_0040: ret

  using System; 

  using System.Text; 

  namespace ConsoleApplication1 { 

  class Class1 { 

  [STAThread] static void Main(string[] args) { 

  string a = Console.ReadLine(); 

  string b = Console.ReadLine(); 

  string c = Console.ReadLine(); 

  StringBuilder sb = new StringBuilder(a); 

  sb.Append(b); 

  sb.Append(c); 

  Console.WriteLine(sb.ToString()); 

  string string2 = a+b+c; 

  Console.WriteLine(string2); } } }