Convert COBOL to C#

Conversion Samples of COBOL to C#

Ispirer Toolkit analyzes all object dependencies during the conversion process and provides not only line-by-line conversion, but resolves type conversions as well. The software understands and transforms the necessary inheritance dependencies. It parses the entire source code, builds an internal tree with all the information about the objects, and uses it in the migration process.

To convert structures, we have implemented additional type conversion classes to store variable sizes to convert redefines and arrays so that they work similar to COBOL logic.

The code samples below provide you with more details.

• Common variables declaration structure conversion:

  COBOL

   
  01 varlnk.
    05 varlnk-1 PIC 999.
    05 varlnk-2 PIC X(10).
    05 varlnk-3 PIC 9(7).
   

  → C#

   
          public VarlnkType Varlnk = new VarlnkType();
   
      public class VarlnkType : Record
      {
          public IntField Varlnk_1 = new IntField(3);
          public StrField Varlnk_2 = new StrField(10);
          public IntField Varlnk_3 = new IntField(7);
      }
   

• Common REDEFINES conversion:

  COBOL

   
  01 var1 PIC XXX  VALUE '111'.
  01 var2 REDEFINES var1.
    05  vvv1  PIC 9.
    05  vvv2  PIC 99.
   

  → C#

   
          public StrField Var1 = new StrField(3, "111");
          public Var2Type Var2 = new Var2Type();
   
  Var2.Redefine(Var1);
   
      public class Var2Type : Record
      {
          public IntField Vvv1 = new IntField(1);
          public IntField Vvv2 = new IntField(2);
      }
   

• Common array conversion:

  COBOL

   
  01 var5.
     05 var5-occurs OCCURS 2 TIMES.
        10 var5-occurs-txt PIC X(6) VALUE ' TEXT1'.
   

  → C#

   
  public Var5Type Var5 = new Var5Type();
   
      public class Var5Type : Record
      {
          public class Var5OccursType : Record
          {
              public StrField Var5OccursTxt = new StrField(6, " TEXT1");
          }
          public Var5OccursType[] Var5Occurs = (from occurs in Enumerable.Range(1, 2) select new Var5OccursType()).ToArray();
      }
   

• COBOL call chain with PERFORMs conversion:

  COBOL

   
  TopLevel.
      DISPLAY "In TopLevel. Starting to run program"
      PERFORM OneLevelDown
      DISPLAY "Back in TopLevel.".
      STOP RUN.
   
  OneLevelDown.
      DISPLAY ">>>> Now in OneLevelDown"
      PERFORM TwoLevelsDown
      DISPLAY ">>>> Back in OneLevelDown".
   
  TwoLevelsDown.
      DISPLAY ">>>>>>>> Now in TwoLevelsDown."
      PERFORM ThreeLevelsDown.
      DISPLAY ">>>>>>>> Back in TwoLevelsDown.".
   
  ThreeLevelsDown.
      DISPLAY ">>>>>>>>>>>> Now in ThreeLevelsDown".
   

  → C#

   
          private Compatibility CobSmplCblCompatibility;
          private static CobSmplCbl _instance;
          public static CobSmplCbl Instance
          {
              get
              {
                  if (_instance == null)
                  {
                      _instance = new CobSmplCbl();
                  }
                  return _instance;
              }
          }
          public CobSmplCbl()
          {
              _instance = this;
          }
          public void Initialize()
          {
              CobSmplCblCompatibility = new Compatibility();
              CobSmplCblCompatibility.GetAllMethodsInfo(this);
              CobSmplCblProcedureDivision();
          }
          private void CobSmplCblProcedureDivision()
          {
              CobSmplCblCompatibility.InitializeMethodsQueue();
              CobSmplCblCompatibility.CallNextMethod(this, true);
          }
          private void Toplevel()
          {
              Console.WriteLine("In TopLevel. Starting to run program");
              CobSmplCblCompatibility.PerformThru(this, "Oneleveldown");
              Console.WriteLine("Back in TopLevel.");
              Console.ReadKey();
              Environment.Exit(-999);
              CobSmplCblCompatibility.CallNextMethod(this, true);
          }
          private void Oneleveldown()
          {
              Console.WriteLine(">>>> Now in OneLevelDown");
              CobSmplCblCompatibility.PerformThru(this, "TwolevelsDown");
              Console.WriteLine(">>>> Back in OneLevelDown");
              CobSmplCblCompatibility.CallNextMethod(this, true);
          }
   
          private void Twolevelsdown()
          {
              Console.WriteLine(">>>>>>>> Now in TwoLevelsDown.");
              CobSmplCblCompatibility.PerformThru(this, "Threelevelsdown");
              Console.WriteLine(">>>>>>>> Back in TwoLevelsDown.");
              CobSmplCblCompatibility.CallNextMethod(this, true);
          }
          private void Threelevelsdown()
          {
              Console.WriteLine(">>>>>>>>>>>> Now in ThreeLevelsDown");
              Quickfile_sqlCompatibility.CallNextMethod(this, true);
          }
   

Copy statement conversion

During the conversion stage, the code from the copy files is included in the program and replaced with the appropriate copy statements, thereafter the program converts the entire code.

• If statement conversion:

  COBOL

   
    if  var3 = var4
        move "D" to var3
    else
        move " " to var3.
   

  → C#

   
              if (string.Compare(Var3.Value, Var4.Value) == 0)
              {
                  Var1.Value = "D";
              }
              else
              {
                  Var3.Value = " ";
              }
   

• PERFORM UNTIL statement conversion:

  COBOL

   
    PERFORM UNTIL IterCount = 5
       ADD 1 TO IterCount
    END-PERFORM
   

  → C#

   
              while (!(Itercount == 5))
              {
                  Itercount = Itercount + 1;
              }