.net - Fujitsu COBOL 中的迭代 Systems.Collections.List

Question

如何循环访问集合？

我使用的是 Fujitsu/Alchemy 编译器的试用版，但供应商的支持缓慢且糟糕。

我基本上想将一个列表从 C# 传递到 COBOL，然后让 COBOL 使用它并可能更新它。

在 C# 中，迭代集合的正常方法是使用“foreach”构造。

但是，C#“foreach”构造是以下内容的快捷方式:

private static void test1()
{
    List<IDMSMapField> list1 = new List<IDMSMapField>();
    int listSize = list1.Count;
    // was just checking exact variablename and case here to copy into COBOL code.
    int itemNumber = 0;

    System.Collections.Generic.List<IDMSMapField>.Enumerator enumerator1 = list1.GetEnumerator();

    while (enumerator1.MoveNext())
    {
        Console.Write("Okay" + enumerator1.Current);
    }
}

如果你能帮我弄清楚如何声明这个类，我可以用 COBOL 编写这个:

System.Collections.Generic.List<IDMSMapField>.Enumerator

“枚举器”结构是 documented on Microsoft's MSDN site .

它告诉我们“Enumerator”是一个结构，而不是一个类!

据我在手册“CreatingCOBOLfromDotnetFrameworkDox.pdf”中所知，结构被定义为 COBOL 存储库中的类。

手册中的示例:

Define specifiers for structure in REPOSITORY, and any struct members:
CLASS STRUCT-name AS "struct-namespace"
PROPERTY PROP-struct-member AS "external-property-name"
Handle structures like classes. E.g. object to store a struct instance:
01 struct-object OBJECT REFERENCE STRUCT-name.

下面，我重复了一些我尝试过但都无法编译的变体，因为“无法解决”错误。如果你能告诉我如何正确声明这一点，我认为我们可以继续前进。

1.

    REPOSITORY.
           CLASS  CLASS-LIST         AS "System.Collections.Generic.List<>"
           CLASS  STRUCT-Enumerator  AS "System.Collections.Generic.List<>.Enumerator"
           .

第二行错误:

error JMN1795I-S: The named reference 'System.Collections.Generic.List<>.Enumerator' cannot be resolved.

1. 与此完全相同的错误:

       REPOSITORY.
              CLASS  CLASS-LIST         AS "System.Collections.Generic.List<>"
              CLASS  STRUCT-Enumerator  AS "System.Collections.Generic.List<T>.Enumerator"
              .
   

error JMN1795I-S: The named reference 'System.Collections.Generic.List.Enumerator' cannot be resolved.

1. 同样的错误:

   存储库。 CLASS CLASS-LIST AS“System.Collections.Generic.List<>” 类结构枚举器为“System.Collections.Generic.List.Enumerator” .

error JMN1795I-S: The named reference 'System.Collections.Generic.List.Enumerator' cannot be resolved.

另一种选择是将其视为数组，但我也坚持这一点。

REPOSITORY.
    CLASS LIST-IDMSMapField    AS "System.Collections.Generic.List<>[]"
    CLASS CLASS-IDMSMapField   AS "Lightyear.ERCB.IDMSDC.IDMSMapField"
    CLASS CLASS-LIST-IDMSMapField EXPANDS LIST-IDMSMapField USING CLASS-IDMSMapField.

METHOD-ID. TW1DR4000-PF06 AS "TW1DR4000_PF06".
DATA DIVISION.
WORKING-STORAGE SECTION.

01 MapFieldItem USAGE OBJECT REFERENCE CLASS-IDMSMapField.

LINKAGE SECTION.

01 MapFieldList USAGE OBJECT REFERENCE CLASS-LIST-IDMSMapField.

PROCEDURE DIVISION...
...
SET MapFieldItem TO MapFieldList(1).

error JMN2671I-S: ':' must be specified in the reference modifier. ':' is assumed.

我认为编译器可能将 (1) 视为子字符串操作。

Answer 1

这花了一段时间，但这是一个完整的工作示例。还有其他一些获取属性的技巧，并使用正确的 USAGE 子句将属性值(例如 Count)移动到 COBOL 变量。“EXPANDS”关键字(在存储库中)是该解决方案的另一个关键部分。

在我的实际程序中，我将在 LINKAGE 部分收到列表，并且我将有一个更复杂对象的列表...但示例代码是一个更简单的场景，独立运行并“作为是”。

   IDENTIFICATION DIVISION.
   PROGRAM-ID. MAIN AS "COBOLEnumerationSample.Main".
   ENVIRONMENT DIVISION.
   CONFIGURATION SECTION.
   SPECIAL-NAMES.
   REPOSITORY.
       CLASS List        AS "System.Collections.Generic.List<>"
       CLASS SysString   AS "System.String"
       CLASS SysBoolean  AS "System.Boolean" 
       CLASS ListString EXPANDS List USING SysString
       CLASS Enumerator  AS "System.Collections.Generic.List<>+Enumerator"
       CLASS StringEnumerator EXPANDS Enumerator USING SysString
       PROPERTY PROP-Count   AS "Count"      
       PROPERTY PROP-Current AS "Current"
       .       
   DATA DIVISION.
   WORKING-STORAGE SECTION.
   01 myList              OBJECT REFERENCE ListString.
   01 myEnum              OBJECT REFERENCE StringEnumerator.   
   01 myBooleanEnumResult OBJECT REFERENCE SysBoolean. 
   01 myDotNetString      OBJECT REFERENCE SysString.  
   01 myLoopCounter       PIC 9(4)  value zero. 
   01 myCobolCount        PIC S9(9) COMP-5 VALUE ZERO.
   01 myCobolString       PIC X(30) value spaces. 
   01 YN-END-LOOP         PIC X     value "N". 
   01 WS-ACCEPT-INPUT     PIC X(80) value spaces. 

   PROCEDURE DIVISION.
   1000-START.
       INVOKE ListString "NEW" returning myList.
       INVOKE myList "Add" using "Apples"
       INVOKE myList "Add" using "Bananas"
       INVOKE myList "Add" using "Orange"


       SET myCobolCount to PROP-Count of myList 
       DISPLAY "Size of MyList = " myCobolCount

       INVOKE myList "GetEnumerator" returning myEnum.


       PERFORM UNTIL YN-END-LOOP = "Y" 
             INVOKE myEnum "MoveNext" returning myBooleanEnumResult  
  * How to test for Boolean, True = B'1' and False = B'0' 
             IF myBooleanEnumResult = B'0' 
                MOVE "Y" TO YN-END-LOOP 
             ELSE       
                SET myDotNetString TO PROP-Current of myEnum 
                ADD 1 TO myLoopCounter
                SET myCobolString to myDotNetString 
                DISPLAY myLoopCounter " " myCobolString 
             END-IF    

       END-PERFORM 

       DISPLAY "END OF PROGRAM - PRESS ENTER TO END" 
       ACCEPT WS-ACCEPT-INPUT
       .

   END PROGRAM MAIN.