Q139863: How to Determine the Variable Type

Article: Q139863
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0
Operating System(s): 
Keyword(s): kbcode
Last Modified: 10-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 3.0 
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SUMMARY
=======

When using the Visual FoxPro TYPE() function, you must ensure that the
expression passed to the function is always be of the character type. You can
use a user-defined function (UDF) to determine the type of a variable without
trying to convert the variable to a character string. This article shows you how
to do it.

MORE INFORMATION
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Step-by-Step Example
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1. Open a program file, and type the following function into it:

     FUNCTION ALLTYPE
      *
      *  Purpose:  Determine the data type of a variable
      *  Syntax:   m.cNewValue = ALLTYPE(<Variable Name>)
      *  Parms:    xxx (Can be Character, Numeric, Date, or Logical)
      *            The variable for which the type is to be determined.
      *  Return:   lcType:  C for Character
      *                     N for Numeric
      *                     D for Date
      *                     L for Logical
      *  Example:  lcTheType=ALLTYPE(Variable)
      *
      PARAMETER xxx
      local llType,lcType
      lcTemperror=ON('ERROR')
      ON ERROR llType=.f.
      llType=.T.
      xxx=xxx+" "
      IF llType
        lcType="C"
      ENDIF
      llType=.T.
      xxx=!xxx
      IF llType
        lcType="L"
      ENDIF
      llType=.T.
      xxx=xxx+1
      IF llType
        lcType="N"
      ENDIF
      llType=.T.
      xxx=MONTH(xxx)
      IF llType
        lcType="D"
      ENDIF
      ON ERROR &lcTemperror
     RETURN lcType

2. The value returned is N.

The TYPE() function may be used to obtain the same result if the variable is
placed enclosed in quotation marks. For example, the following will also return
N:

     ? TYPE('x')

Additional query words: VFoxWin

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Keywords          : kbcode 
Technology        : kbVFPsearch kbAudDeveloper kbVFP300
Version           : WINDOWS:3.0

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