条件：RPG中的正数和负数

Question

当我在我的控制台中输入一个负数时，我没有得到显示！例如，如果输入值“-2”，我不会收到消息“negative”

在积极和无效的情况下都可以

 H
 D Number          S              2S 0

  *
  /Free

      dsply 'Enter your number please : ' '' Number;

      If (Number > 0);
         dsply 'Positive';

      ElseIf (Number = 0);
         dsply 'Null';

      Else;
         dsply 'Negative';
      ENDIF;

      *inlr = *on;

  /End-Free

Answer 1

在 DSPLY 操作码的 RPGLE 参考中，我找到了这个摘录：

If a non-float numeric field is entered with a length greater than the number of digits in the result field and the rightmost character is not a minus sign (-), an error is detected and a second wait occurs. The user must key in the field again.

DSPLY 操作码似乎希望减号在尾部而不是前导。

Answer 2

如果您在 DSPLY 消息上执行 F1（帮助），它会显示：

Message ID . . . . . . :   RNQ5337       Severity . . . . . . . :   00         
Message type . . . . . :   Sender copy                                         
Date sent  . . . . . . :   12/18/20      Time sent  . . . . . . :   12:42:16   
                                                                               
Message . . . . :   DSPLY  Enter your number please :      0                   
Cause . . . . . :   This is an inquiry message originated from RPG procedure   
  MY_PGM in program MY_LIB/MY_PGM. The program is expecting a numeric 
  input field with a maximum length of 2 digits with 0 decimal positions.  Do  
  not type in a decimal point when entering data. When entering negative data, 
  type a negative sign ('-') immediately after the last digit of the data.

Answer 3

您可以使用 %dec() to convert a numeric value in a string to a numeric variable. That will allow your users to place the negative sign on the left or the right. This might be a friendlier way of using the DSPLY 操作码。

**FREE
   //simple demo, not worrying about exceptions

   dcl-s myStr  varchar(5);
   dcl-s myNum  packed(3:0);


   dsply 'Enter your number please : ' '' myStr;
   myNum = %dec(myStr:3:0);

   Select;
   When (myNum > 0);
     dsply 'Positive';

   When (myNum = 0);
     dsply 'Zero';     // not the same a null ;-)

   Other;
     dsply 'Negative';
   EndSl;

   *inlr = *on;
   RETURN;

条件：RPG中的正数和负数

Condition: positive and negative number in RPG

rpg

rpgle