useStreamReader to read text from a file

1. in c++ environment

 1 using namespace System;
 2 using namespace System::IO;
 3 int main()
 4 {
 5    try
 6    {
 7       // Create an instance of StreamReader to read from a file.
 8       StreamReader^ sr = gcnew StreamReader( "TestFile.txt" );
 9       try
10       {
11          String^ line;
12
13          // Read and display lines from the file until the end of
14          // the file is reached.
15          while ( line = sr->ReadLine() )
16          {
17             Console::WriteLine( line );
18          }
19       }
20       finally
21       {
22          if ( sr )
23             delete (IDisposable^)sr;
24       }
25    }
26    catch ( Exception^ e )
27    {
28       // Let the user know what went wrong.
29       Console::WriteLine( "The file could not be read:" );
30       Console::WriteLine( e->Message );
31    }
32 }

2.c# environment

 1 using System;
 2 using System.IO;
 3
 4 class Test
 5 {
 6     public static void Main()
 7     {
 8         try
 9         {
10             // Create an instance of StreamReader to read from a file.
11             // The using statement also closes the StreamReader.
12             using (StreamReader sr = new StreamReader("TestFile.txt"))
13             {
14                 string line;
15                 // Read and display lines from the file until the end of
16                 // the file is reached.
17                 while ((line = sr.ReadLine()) != null)
18                 {
19                     Console.WriteLine(line);
20                 }
21             }
22         }
23         catch (Exception e)
24         {
25             // Let the user know what went wrong.
26             Console.WriteLine("The file could not be read:");
27             Console.WriteLine(e.Message);
28         }
29     }
30 }