LogiView

Function 'scan'

This function splits up a forwarded string into individual substrings which are assigned to corresponding variables according to the type by means of conversion. The result is the number of sucessfully assigned variables.

The function is aborted if the format character string has been comletely processed or if a field in the input string is not appropriate to the conversion specifications.

A substring extends to the next space, tab (\t) or line break (\n) or to an explicitely specified field width.

Every conversion specification starts with the % character and ends with a conversion character. The space between % and the conversion character could contain the following (in sequence):

*	An asterisk preventing the allocation of a field to a variable. (In this case the number of output variables is lower than the number of fields in the input string.)
Value	A value specifying the maximum field width.

The following letters are used as conversion characters:

i, d	Converts a field to an integer expression.
f	Converts a field to a float expression in float-point representation with six digits behind the decimal point. Rounding errors cannot be excluded.
s	Converts a field to a string expression. In this case only the explicitely specified field width is queried if necessary.
l	Converts a field to a logic expression. The following fields can be converted to the logic value 'TRUE': TRUE, Y, y, J, j, O, o.
	The following fields can be converted to the logic value 'FALSE': FALSE, N, n.

scan is based on the ICU function u_sscanf, so please check the ICU documentation for details on the supported patterns (see the ICU Homepage at http://site.icu-project.org/home).

This function must be called in the action part only!

To support I18N, the "u_sscanf" function replaces the standard C function 'sscanf'.

For difference and limitations resulting from this change, refer to the Oracle Support Knowledgebase at https://support.oracle.com

Syntax:

{INT_VAR}= scan({STR_EXPR},{STR_EXPR},{VAR_LIST})

I/O parameters:

	{STR_EXPR}	Input string
	{STR_EXPR}	Format character string (string expression)
	{VAR_LIST}	Output variables, assigned with the converted fields of the input string (types according to the corresponding field).

{INT_VAR}

Number of assigned substrings

Example 1:

Declaration of Variables

 10 DOCU_STRING_1 = "45.5 |ABCD 4711 | 33mm"	
 20 DOCU_INT_1 = scan(DOCU_STRING_1,"%f %*s %4s | %i",
                      DOCU_FLOAT_1, DOCU_STRING_2,DOCU_INT_2)
 30 put(DOCU_FLOAT_1,DOCU_STRING_2,DOCU_INT_2)

Result:

Substring	45.5	\|ABCD	4711	\|	33mm
Format character string (string expression)	%f	*%s**	%4s	\|	%i
Explanation	The substring is converted to a float value	The substring is skipped due to the "*" character.	The substring is converted to 4-digit string value	The substring is skipped due to an aquainted character.	The substring is converted to an integer value
Variables	DOCU_FLOAT_1	-	DOCU_STRING_2	-	DOCU_INT_2
Allocation	45.5000000	-	4711	-	33

Besides the conversion information '%i', '%f', '%l' and '%s' also regular expressions contained in the ICU standard function 'u_sscanf' are supported. A LogiView string variable must always be included as related output argument. The following conversion information can be used:

%[Character]

Displays only those characters included in the brackets.

%[^Character]

Displays only those characters not included in the brackets.

The list of characters corresponds to a simple listing or a (ascending) range:

ABCDabcd or A-Da-d	The first four characters of the alphabet in upper case or lower case.
0123456789 or 0-9	only numbers
It is possible to combine both possibilities.

Example 2:

Declaration of Variables

 10   DOCU_STRING_1 = "abc*\defg" 
 20 C -- No special characters must be used
 30   DOCU_INT_1 = scan(DOCU_STRING_1,"%[A-Za-z0-9]", DOCU_STRING_2) 
 40   put(DOCU_STRING_2)

Result:

Functions and commands: Editing Strings